'AITA if I tell my ex’s fiancée that he cheated on both of us?'

"AITA if I tell my ex’s fiancée that he cheated on both of us?"

My ex and I were together for almost 10 years. For months, we planned that I would finally move in with him. Two weeks before the move, he broke up with me. I later found out he had been seeing someone else the whole time, which he always denied.

While we were talking about moving in together, he was on dating apps and eventually started a relationship with another woman. I also supported him financially for years and lent him money.

He made me feel like I was the problem for “not wanting to move in,” when in reality I just wanted real commitment. The moment I told him I was moving in two weeks, he ended things. He told me that he wasn’t leaving for anyone. Now, I got to knew the truth when they got engaged.

Part of me thinks she deserves to know the truth. Another part of me feels relieved she took him out of my life, since I now see how much he took advantage of me.

Should I tell her, or let it go and move on?

Here's what people had to say to OP:

jennyfromtheblock wrote:

You can, but be prepared for if she already knows and doesn't give a crap.

That's what happened to me.

Addaran wrote:

NTA. She deserves to know. If you dont tell her, you are the asshole. Both morally and for health reason she deserves to know. She never consented to the additional risks of him having more partners ( just like you didnt). And if he cheated on you and her at the same time, chances are he will cheat again in the future.

Traditional_Fan_2655 wrote:

NTA, feel free to have your revenge, but let it teach you a few key life lessons. Never ever support another adult that is not your child attending school or needing a BRIEF assistance or a disabled parent. A partner only receives full support during brief education improvements or if they are the SAHP.

Once someone cheats or attempts to cheat, don't even wait for the excuses. Being on apps is cheating, even if no one else wanted them. The intent was there. Also, they wouldn't be truthful about it anyway.

Leave ASAP and don't look back no matter the tears, begging, apologies, or excuses. If they don't respect you enough to honor their commitment or to leave first, they will never respect you for returning. You deserve better.

Greyparzi wrote:

NTA. Personally, I’d want to know if my partner was cheating on me—or had a history of cheating—before getting married. I think it’s important for her to at least be aware, because what’s stopping him from doing it again? The fiancée deserves to know. And honestly, whether the motive is revenge or genuinely looking out for her doesn’t change the fact that she has a right to that information.

CPSue wrote:

IMO, unless you’re absolutely sure she didn’t know anything about you, you should stay out of it. Even then, I’d leave it alone because she probably wouldn’t believe you.

The two of them most likely deserve each other. It’s hard to believe that she didn’t know he already had a girlfriend. It’s even harder to believe that she hasn’t figured out that there had to be some overlap between relationships at some point. You aren’t TA no matter what you do, but I doubt an intervention would work. You don’t need the drama.

SirGuestWho wrote:

Would it help you, her or your ex if you did or is it just for revenge? Do you know what he has told her about you if anything? Personally whilst I understand your anger at what he did I would caution against saying anything now but NTA if you did say something. I just don't think it will give you what you want.

TheDIYEd wrote:

Yeah YTA. Just move on with your life? Whats the game plan here? Any time he gets in a relationship you will be there to “warn” them? You ate not doing this from the goodness of your heart, you are just in for revenge. You don’t just find out your ex, current status. You ate activity staking him for information. I have literally 0 idea about any of my previous partners, if they are alive at all.

KirikaClyne wrote:

NTA if you do it. I was cheated on for years, and she even knew we were married. She didn’t care.

In the end, it won’t make you feel any better. It better to just move on with your head held high.

BoyAstroAstro wrote:

This feels like that one scene in Scott Pilgrim where Ramona says “you cheated on both of us?” And Scott says “no I cheated on Knives with you” and when Ramona says what’s the difference he tells her she wasn’t wrong.

Like he cheated on you with her and she has no idea so he probably feels like it was fine or if she never finds out its good, but you also waited until they were engaged to say something. If you would’ve said something the second they went public it would’ve made an impact but now if you say anything you may just seem like the desperate ex. Let it be.

ExternalRip6651 wrote:

If you have concrete evidence you can provide, send it anonymously. She deserves to know, but only if you can back it up. If it’s just your word against his, it’s likely not going to do much and have more backlash. There’s still a decent chance it’ll be traced back to you if it’s anonymous, so take precautions and be careful.

Complete_Ad5483 wrote:

Yes, in this instance you would be TA.

However there is nothing wrong with being petty….go full scorched earth…include the family and friends if you really want to make an impact!