'AITA for refusing to help my sister after she left her husband for his best friend?'
"AITA for refusing to help my sister after she left her husband for his best friend?"
firakti
I’m dealing with some real family drama and could use an outside perspective. My sister, Emily (30F), has left her husband, Mark (30M), to be with his best friend, Tom (32M). Now she’s asking if she can stay with me, and I honestly have no idea if I’m being unreasonable by saying no.
A bit of background: Emily and Mark have been together since high school. They were one of those couples everyone thought was perfect—together for over a decade, married for five years, and completely solid (or so we thought).
Mark is a genuinely good guy. He’s the type who’d drop everything to help someone out, has patched up my parents’ roof more times than I can count, and has been there for me through my own worst breakups.
He’s basically part of our family, and we’ve all grown to love him like a brother. Well, it turns out that about a year ago, Emily and Tom (Mark’s best friend) started “connecting” in a different way.
I think it began as them confiding in each other about their “marriage struggles,” and at some point, they convinced themselves that they were each other’s “soulmates.” Emily swears it wasn’t physical until recently, but knowing it’s been going on emotionally for so long honestly feels worse.
The kicker? Emily didn’t even tell Mark herself. Tom’s wife, Lisa, was the one who walked in on them together. She’s the one who told Mark—not Emily. She claims she didn’t want to hurt him, so I guess she thought… what?
That he’d just not notice his wife left him? I don’t know. It was a disaster. Mark was crushed, blindsided. He tried calling Emily to talk, but she’d already packed her things and left to stay with a friend, saying she was “finally following her heart” and that she doesn’t “owe anyone an apology.” Honestly, it all felt cold.
Now Emily’s asking to stay with me because, according to her, Mom and Dad are being “hostile” and “unsupportive.” They’re both furious with her, especially my dad, who feels like she’s broken up our family and betrayed someone who’s been nothing but kind to us.
But my mom’s in that weird spot of still being her mother and saying she needs support, despite what she did. I told Emily I’m not comfortable letting her stay here. For one thing, my fiancé is close friends with Mark.
It would feel like a betrayal to let her stay when we know how badly she hurt him. My fiancé actually said it would be a slap in the face, and I agree. But it’s not just loyalty to Mark—this whole thing has shaken how I see my sister.
We were close growing up, but the way she’s handling this… how easily she’s justified tearing someone’s life apart, and her complete lack of remorse—it feels like I don’t even know her anymore.
When I suggested she should give Mark some closure, she lashed out, called me “just like everyone else,” and accused me of “throwing her under the bus.” She even dragged up mistakes I made years ago, saying I’m a hypocrite for not being “forgiving.”
A part of me does feel guilty. I know what it’s like to feel lost and rejected, and there’s a small part of me that wonders if maybe she’s really in a dark place and I’m abandoning her when she needs family most.
But there’s a bigger part of me that thinks I’d be enabling her selfishness if I let her stay. She made this mess, and helping her now feels wrong when I see all the damage she’s left behind.
So now our family is split. My mom keeps saying, “family sticks together,” and thinks Emily will regret this someday. But my dad doesn’t even want to talk to her. He thinks she needs to “face the consequences” of her choices, and he’s said he’s ashamed of her behavior.
Meanwhile, I feel like whatever I do, I’m betraying someone. If I let her stay, I’m betraying Mark, my fiancé, and honestly my own values. I don’t want to act like what she did is okay. But if I refuse, I feel like I’m abandoning my sister, and I’m scared I’ll regret it if she spirals.
When I told her she couldn’t stay, she got cold and said I’m “just like everyone else,” judging her without understanding what she’s going through. She keeps saying she feels totally alone and that I’m the last person she thought would turn her away. It’s hard to hear that, but every time I picture Mark, blindsided and brokenhearted, I feel sick all over again.
I’m struggling to figure out if I’m doing the right thing. Do I support my sister, even after all this, because she’s family? Or am I justified in setting this boundary because of the hurt she’s caused and her refusal to own up to it?
I genuinely can’t tell if I’m being fair or if I’m letting my own anger cloud my judgment. AITA for refusing to let my sister stay with me, even if it risks our relationship?
Here were the top rated comments from readers in response to the OP's post:
There's this Korean poetry that says "When you're invite someone to your life you're inviting their whole life with them". Honestly OP you're not responsible for this grown up woman who should work to pay some rent.
Her lack of planning doe's not constitute an emergency for you. She should plan better if she wanted to leave her husband. Where's the homewrecker guy? He should be dealing with her. Stop inviting the chaos for your life.
Are you're trying to sabotage your own relationship? Cuz your boyfriend will think you as someone who's support a cheater = cheater. NTA and please, stop falling for the guilt trip. She's not homeless, she's not sick. Being a selfish coward B it's not an emergency.