'I just found out my fiance and I are related, and we don't know what to do.' MAJOR UPDATE

"I [F22] just found out my fiance [M22] and I are related, and we don't know what to do."

I never thought I would post here, but the holidays uncovered something huge and my fiancé and I genuinely have no idea what to do. I grew up in a fairly large city in the south with just my mom, my younger brother, and me.

My dad passed of cancer when I was four, and my mom supported us by working as an accountant for a mid-sized company. It was always just “the big three,” as my mom liked to say. I have never known anyone from her side of the family.

She has always been extremely private about her upbringing, but as I got older I picked up bits and pieces. Whenever we saw family, it was always my dad’s side. My parents met as adults, but after my dad died, my grandpa really stepped up in my life. He took me to father-daughter dances, came to baptisms and major milestones, and was always present.

When I asked about my mom’s side of the family, I usually got short answers like “they’re bad people” or “we live far away for a reason.” As far as I know, my mom left home when she was around 17 and never spoke to anyone from her family again. My grandparents on my dad’s side never met anyone from her side.

Almost four years ago, I got into a great university far from home. My grandpa drove me down to campus and helped me move in. During orientation, I met Tom (not his real name). We clicked instantly. Same humor, same values, and a connection I had honestly never felt before. We became best friends very quickly and soon started dating.

Tom is also from far away, but our hometowns are extremely far from each other. Over the years, I spent some holidays with his family and he spent some with mine. My mom, my brother, and my grandpa (who passed away around Thanksgiving this year) all adored him and were very vocal about wanting me to marry him.

His family accepted me just as warmly. Last year, his parents even gave him a large gift to help pay for an engagement ring. He proposed this past August, right around the anniversary of when we met. We are planning to get married in June, shortly after we graduate. One more piece of context before the actual problem. Tom and I became sexually active about a month ago.

We were both virgins when we met and had decided we wanted to wait until marriage. After he proposed, we decided together that we were comfortable taking that step, especially since I am on birth control and we were already planning a wedding. Our parents assume we are waiting, but no one has ever directly asked. Until now, this has not been a point of stress for us.

Here is where everything falls apart.

This past Christmas, I stayed with Tom’s family.

My mom and my paternal grandmother are in the middle of an argument I did not want to be involved in, and my mom was completely fine with me going elsewhere. While at Tom’s family gathering, his mom’s parents came over and we all had a big holiday meal, opened gifts, and had a great time. They even gave me several gifts with their last name on them.

At some point during the evening, Tom’s grandmother made a comment to his mom, who I will call Melissa. She said, “Melissa, do you remember when you and Rachel got me that planter for Christmas?” I leaned over and quietly asked Tom who Rachel was. He looked confused and said it was his mom’s twin sister, who disappeared years ago. He had never met her.

I immediately felt uneasy. My mother’s name is Rachel, although she has gone by her middle name my entire life. I also knew she had siblings, one sister and one brother. Tom had mentioned an uncle who passed away around 2010. At the time, I convinced myself it was just a strange coincidence.

Later that night, people were moving around the house and Tom and I ended up sitting alone together with some wine. I whispered something like, “I didn’t know your mom had a twin.” I think at that exact moment it hit both of us. About a year ago, while dating, we had already realized our mothers shared the same birthday. We thought it was funny and even mentioned it casually once to his mom.

We both started internally freaking out but kept it together for the rest of the visit. The next day, I flew home to see my mom. Before I got there, Tom and I came up with a plan. I told my mom I had been talking to my gynecologist about some issues with my period and that one of the intake questions asked whether there were twins in my family. I said I didn’t know and figured I should ask.

For the first time in my life, my mom admitted she was a twin. When I asked why she never told me, she went on a long, drunken rant about how her sister Melissa was “a literal demon.” My mom is, unfortunately, drunk most of the time. She also mentioned cutting her family off completely when she was young.

What is wild is that my mom and Tom’s mom look absolutely nothing alike. One is tall and brunette, the other is short and blonde. At that point, everything clicked. We confirmed last names, which were the same. I also learned my mom’s maiden name for the first time in my life, which I know is strange, but she is intensely private.

Tom and I are first cousins. We have no idea what to do next. Our parents have never met, but they are supposed to meet at our wedding in six months. We have already built a future around each other. Tom has a great job lined up, and I have been accepted early decision to my dream law school in the same city. Our relationship is genuinely strong. We are best friends and deeply in love.

Ending the relationship feels like throwing away the greatest joy either of us has ever had. Continuing it feels terrifying. There are obvious biological concerns if we ever want children. There is also the very real possibility of being disowned or pressured to split once the truth comes out. We are stuck and completely overwhelmed. What do we do?

Edit 1: Thanks for all the kind comments. Tom and I have read through all of them, and we really appreciate the thoughts. We have decided to talk to our parents tonight. We both fly back to college tomorrow, so it's really the last time we can do this before it gets dangerously close to the wedding.

I'll give an update on how it goes either tonight or tomorrow at the airport. We plan to tell them what we've learned, but insist it won't affect our plans to marry. Hopefully, if we lead with that, there won't be an effort to break us up.

Here's what people had to say to OP:

jensmith20055002 wrote:

I’m sorry that sounds incredibly painful and also the plot of a movie.

OP responded:

I certainly feel like I am living in a horror movie :/

Knightoftherealm23 wrote:

As I have said above the cousin thing is one thing but your mother meeting her estranged twin at your wedding is going to cause absolute carnage. This must be aired before the wedding and you need to face the possibility of your mother making you choose, you say she's drunk most of the time so I'm guessing she isn't the best mum else you wouldnt have added that information.

Tom's mother also needs to know. Or there is another option. You tell your mother. She demands you choose. You choose Tom, disinviting your family to the wedding. You say nothing to Tom's mother. Its not recommended but this is all going to go disasterously wrong. I think if I could accept he was my first cousin id just elope and keep the families separate as far as possible.

OP responded:

I fear if we tell our mothers then our whole support system will fall out beneath us if we don't break up. Its almost like we have to be willing to break up if we tell them, and neither of us want to break up at all.

philla1 wrote:

Do one of those DNA tests and see how much DNA you share. My grandparents found out they were 3rd cousins after they got married. Their parents knew as well. Not quite the same but they made it work.

OP responded:

This is good advice, but there's also some blissful ignorance here. Like at what % do we draw the line?

CookieMama28 wrote:

I’m sure all of this is very overwhelming. I strongly recommend speaking to your mother alone and being upfront. You’ve done nothing wrong, no one planned this. She’s shunned her family for a reason and it would be catastrophic if she walked into your wedding venue and saw people she never expected to see.

Biologically, some first cousins have had children with no genetic issues and many first cousins have had healthy marriages. You didn’t grow up together so there’s no familial emotion involved. Therapy all round may be a good option.

OP responded:

I fear if my mother knows then she will force a choice between "Tom" and her.

Bonegirl06 wrote:

As long as it's legal I'd continue as planned. Cousins married for most of history. Even your kids if you have them won't pop out looking like Hapsburgs. It takes many generations of close marriages to really screw up the tree. You could always choose to nix the wedding and elope.

Not long after posting, OP shared an update.

Update 1/4/26 8:40 EST: I didn’t expect this story to get so much attention, but I appreciate all the kind words and encouragement. I also appreciate everyone who reached out kindly in my DMs. Sorry if I haven’t responded yet. As you’ll soon read, my life is a little upside down.

I wrote the original post in the early afternoon. At the time, my mother was out buying my brother new clothes for his upcoming semester. I decided I would confront her after dinner. Tom and I agreed that I would tell my mom that night, and then we would figure out how to tell his parents. Dinner came, and I wasn’t eating.

My brother kept asking why, so I eventually gave in and told my mom I had something important I needed to talk to her about privately. She seemed to recognize the seriousness of my tone and told my brother to go to the gas station to buy scratchers. When he left, I told her everything, starting with, “This is really big news, but I want you to know that I intend to continue my relationship with Tom.”

I told her I had been at Tom’s house and learned that Tom’s mom had an estranged twin, and that I was confident it was her.

I said the full legal names of Tom’s mom and his maternal grandparents. I knew I was right by the shade of red my mother turned.

She kept saying, “What?” and “Is this a joke?” I even showed her Tom’s mom’s Facebook. My mother has no social media and never has, as far as I know. At first, my mom went silent while I sobbed. Then she erupted. She told me I needed to leave Tom immediately and never speak to him again. I told her I wasn’t going to do that.

She started yelling about how Tom’s family was spreading lies about her to me. They do not even know. She was being paranoid. I told her I didn’t need to tell them anything, that she could keep this secret and simply never meet them. Since his family is paying for the entire wedding, I suggested she not attend, so she would never have to interact with them. That suggestion was not taken well.

She called me every name in the book. Wh0re, liar, b-word, c**t, etc. She screamed at me until she was blue in the face and told me she would not allow me to return to school for my final semester. Around this time, my brother came home. He is a pretty low key guy and does not handle conflict well, so he went into the adjacent living room and scrolled on his phone.

I told my mom I would marry Tom regardless, and that if she chose not to be part of my life, that was her decision. She called me ungrateful and continued screaming. Things escalated again when she demanded that I hand over my phone. Long story, I am actually on Tom’s family’s plan. She also demanded that I go to my room.

I said no, that I am an adult, and she threw a three quarters full bottle of Botanist gin at me. It hit my arm and shattered on the floor. That is when my brother stepped in and pulled me out of the house. We could hear her breaking things and swearing as we stood outside. Since my flight is scheduled early in the morning, my brother drove me to his friend’s apartment near the airport.

He works at the airport and lives about fifteen minutes away. I had never met his friend before. My mother texted me multiple times asking where I was and calling me awful names again, but nothing else happened. I am writing this now from the airport, waiting to board my flight. I have a bruise on my arm, but it is not serious.

Tom thinks I should have called the cops, but I just could not do that to my mom, even if that ends up being the last time I ever speak to her. My brother brought me all my belongings around two a.m. and then took me to a hotel connected to the airport. He is a saint. This is only half the update. After I left the house, during the drive to my brother’s friend’s place, I called Tom hysterically.

He told me he thought he should tell his parents, and I agreed. After we hung up, around ten thirty p.m., Tom pulled his parents aside and told them everything. They had seen pictures of my mother on my Instagram before and had not recognized her, but once they looked again, they confirmed it was the Rachel they knew.

Melissa cried and cried. Tom’s dad, I will call him Richard, said the situation was very strange. They asked Tom a lot of probing questions, including whether we had been sexual and whether my mother knew. Tom told them everything. They were disappointed in him, but they did not dwell on that.

After Tom explained what had happened with my mom earlier that night, Richard and Melissa completely changed their tone. They told him they still supported our marriage but needed to make a game plan for how to handle this moving forward. They texted me saying incredibly kind things, telling me nothing had changed, that I was still their daughter, and that they loved me.

Melissa also shared why my mom became estranged from them. This is only her side, and I may never hear my mom’s, but apparently when my mom was in high school, she started to unravel emotionally. She would yell at her mother constantly and accuse her of favoring Melissa.

Their father was the coach of the girls’ basketball team, which Melissa played on but my mom did not, and my mom felt rejected by both parents. During their senior year, my mom ran away with an older boy, not my dad. His family knew my grandparents well, so they assumed she was safe, but my mom told them she would never speak to them again, and she kept her word.

The last they heard about her was three years later, when the boy’s parents said they had broken up and she moved to another city. This was the city where she later met my dad. They wrote letters she never answered and eventually respected her wish for no contact.

All of this came secondhand, from Tom, who heard it from his mom, while I was coming down from hysteria in an airport hotel room at dawn. The details may be fuzzy, but that is what I know.

How I’m doing: I’m heartbroken and scared.

I’ve only seen my mother be violent once before, when she threw a brick at my brother for sneaking a girl in. I was always the perfect child, and now I cannot imagine her ever speaking to me again. It feels like I chose the people she felt rejected by over her. My heart breaks for my mom, but I love Tom, and I do not believe it is fair to either of us to abandon this love.

I am also scared of what she might do next. She went to my grandmother’s house and my brother’s girlfriend’s house trying to find me. My brother refused to tell her where I was. She knows where my apartment on campus is. I have considered moving in with Tom for safety, but his parents asked us to stop being intimate until marriage, and I do not think they would approve of us living together.

That said, they have been incredibly kind. They paid for my hotel stay. Tom was nervous about me staying at my brother’s friend’s apartment. I was mostly afraid of the roaches. They are texting me as I write this, sending florist options and talking excitedly about our wedding. Overall, I am okay, but I am terrified of the unknown.

How Tom’s doing: He is very anxious being away from me and incredibly grateful to my brother. He wants me to block my mother’s number, but I am not ready. He encouraged me to make an appointment with my therapist, and we are hoping to attend a few sessions together. He has apologized endlessly and feels like he should have figured this out sooner, but it is not his fault.

If we had known earlier, we might never have had the love we now share, and I believe that love is worth it. This morning, his father warned him not to share this secret with anyone. Tom is nervous about how our grandparents would react if they found out. If anything else happens, I will update again. We are still reading all the comments.

The encouragement, especially from those who urged us to tell our parents, gave us the strength to do the right thing. Even though I regret telling my mother, I think it was better than lying and creating a long term deception. Thank you all for the support. Feel free to ask any questions. It genuinely helps us think through every angle.

Here's what people had to say to the update:

Own-Celebration2439 wrote:

I’m sorry but this won’t end well. I do believe your mother felt left out. Most people never admit to favoring or spending time with one child. She could have spiraled because she felt left out.

She had no right to say those terrible things to you. However if she really doesn’t accept you she could expose your relationship regardless and that’s dangerous especially if you are in a state that doesn’t allow inc**t.

With the mothers being twins you and your fiancee could be biologically siblings not just first cousins. Some twins that don’t look alike are actually biologically identical, it’s rare but happens. If she say something y’all could be arrested, and some places won’t even allow adoption. Please think it through.

oatmilkdischarge wrote:

The fact that you’re still continuing, knowing what you know, is incredibly disturbing. The fact that his parents (your aunt and uncle) support this is equally just as foul.

turbulent-avocado-46 wrote:

Just don't sire kids. The reason why marriage between siblings is frowned on is less about the couple and more about the life quality a child they may have anyways. Though a genetic test is desirable regardless of blood relation if you want kids related to you. While not exactly common, it's still better to know what genetic diseases a child may be predisposed to have.

Salty_Jellyfish17 wrote:

OP, I feel for you, I really do, but I think you should have more pause on the situation than you are presenting. Everything sounds very hectic and overwhelming, and there should be a bigger step back and evaluation than you are describing when it comes to moving forward with the wedding.

Furthermore, the story Tom's mom shared with you screams oversimplification of events. She might not even know that is what she is doing, as she may not know the full story either, but it is definitely incomplete. From the way you describe it, it sounds like your mom may have schizophrenia (this is not a diagnosis or anything, it just aligns with common recountings of schizophrenia onset).

I think other commenters also have a point about where there could have been ab**e or trauma of some kind, which aligns with your mom's functional alcoholism. Overall, you are young, you have time to stop everything and thoroughly take in everything that is happening around you, and think through and evaluate this scenario deeply.

You need to try to get your mom's side of the story and maybe even the POV of Tom's grandparents. You need to slow down and take a long look at everything going on and take it on slowly, step by step, instead of trying to just push through, compromising in some places and ignoring others.