Despite the sister attempting to reconcile five times, the OP repeatedly refused, expressing deep unforgiveness and even wishing ill upon her sister regarding her relationship with the ex-husband. The OP maintained strict no-contact, even refusing to meet the sister’s child. Recently, the sister’s fiancé confronted the OP for not meeting him, leading to a direct confrontation where the sister demanded reconciliation, prompting the OP to state clearly that her feelings had not changed and she would not care if her sister died. This stance has caused conflict with her parents and aunt, leading the OP to question if her actions were too harsh.

Seven years ago my sister had an affair with my (ex)husband. We were still married at the time, I believed happily, and she was his mistress. I caught them together and banished both of them from my life.
I divorced him. I told her to get away from me and the two of them stayed together for a couple of years and had a child.
My sister tried to reconcile with me 5 different times. I rejected her and told her I would never forgive her for what she did and I did call her some names and wish for some bad things to happen to her ie I wished for him to cheat on her and to destroy her life like they did mine and I told her she’d deserve it all and not to cry to me if she caught anything off of him.
I actually did a full STD/STI panel after finding out he’d been cheating on me with her. I was negative but you can never be too careful and he never denied there being more.
I have been 100% no contact with my sister since and I never met her child. Not even when ex cheated while she was pregnant and she ended up homeless. I told our family members I would not accept being around her.
A couple of weeks ago this guy reached out to me. He’s engaged to my sister and was mad I wasn’t there to meet him at the dinner my parents hosted to meet him for the first time. He said my sister was so upset, etc.
That she had wanted me to forgive her, etc. That he felt I was shitty to be mad at her dating an ex of mine. I corrected him and said she was his mistress, that I was married to him, still actively married when they had an affair and I told him I caught them in my home and my bed.
He didn’t reply.
Several days afterward my sister showed up and was pissed off at me for telling him what I did because he left her. She told me I should be willing to put the past behind us and reconcile and to stop treating her like she’s a criminal or evil.
She said I act like she repulses me. I told her because she does. And I told her my feelings had not changed at all in 7 years. She cried and told me one of us could die and we’d never reconcile if I’m not willing to try and I said I would not care.
I told her she could die tomorrow and I would not regret my decision not to reconcile. I told her I no longer cared what happened to her or if she was okay or not. She left in tears.
My parents were so angry she confronted me. They had already been disgusted with her being the other woman but to confront me for correcting her lie, they said it showed she had not grown at all.
While my aunt told me I had no need to be so cruel after time had passed. She told me I’m treating my sister worse than she treated me and that I should be ashamed of myself for saying I wouldn’t care if she died because it’s an evil thing to say to anyone let alone family.
AITA?
Conclusion
The original poster is currently facing strong disapproval from her family because she has maintained seven years of absolute no-contact and expressed extreme finality regarding reconciliation, including stating she would not care if her sister died. The central conflict lies between the OP’s justified need to protect herself from the profound betrayal she experienced and her family’s expectation that the passage of time mandates forgiveness and acceptance, especially toward a sibling.
The core question for debate is whether the OP’s steadfast refusal to forgive, coupled with her harsh final words, is an appropriate boundary protecting her emotional well-being after severe betrayal, or if it crosses a line into excessive cruelty that undermines necessary family ties. Readers must consider where the line between self-preservation and unforgiving hostility should be drawn.
Here’s how people reacted:
Your aunt needs to know that decisions made with malicious intent cannot be undone with an apology.
NTA
I think you should tell your sister that she and your ex-husband ruined your life,
ruined your sense of family and that there is no recovery from it. The trust is gone.
You should also tell her that, she cannot expect you to lie about her, to protect her from her past.
You tell her, you will never do that.
You should also tell her that you however accept that your parents will keep their door open to her, but that you can no longer consider her part of your family, because she destroyed yours.
Question .. did you find a new partner or are you still single? How old are you?
I were you, I’d focus on your life … your personal serenity … You sister needs to do the same without you.
The point remains, Her actions had consequences she wasn’t prepared to deal with. Even NOW she refuses to Own up to what she’s done. She wants You to “get over” her betrayal just because time has passed. Telling her you wouldn’t care if she died Was a bit harsh But 100% justified!
Funny her ex found out the truth from you.
Your sister’s betrayal was profound and life-altering. You have every right to set and maintain boundaries, especially with someone who inflicted such deep pain. Her trying to rewrite history to her fiancé is dishonest, and you were justified in correcting the narrative.
Your response to her confronting you—though harsh—reflects the magnitude of the hurt she caused and your firm stance on protecting your peace. Reconciliation is not owed, regardless of time passed or familial ties. While your words may have been blunt, they were a direct reflection of your truth and boundaries.
The fiancé certainly ate up all his own words! He called you out but he ended up abandoning her himself. LOL
Tell your Aunty you hope she drops dead soon too. How would she like it if someone she loves slept with her sibling & had an affair child? She needs to stay in her lane. Forgiveness is earned & only your parents seem to understand that their cheater daughter has not changed. Who the heck lies to a new man about her circumstances? everyone knows about it. 🤦🏽♀️
Be careful of your parents/family trying to secretly invite her to things to try to force you two to ‘make up’.
This woman is pretty inhuman for her actions. Played stupid games. Found out. It’s a lonely road.
Never give in. Never forget. Way to hold strong.
NTA, this level of betrayal is something you can never come back from especially it being your own sister.
Then again, this person no longer is family to you, so why should you care?
And well, she took the man you loved (at the time), and now because of this she lost the man she supposedly loves… you are not the cause, you are simply the manifest agent of righteous retribution
While her crime – and fuck me, if you’re going going to do it – is shagging your husband, her *stupidity* is letting the new BF within a thousand miles of you. she knows you hold a grudge, and they she makes up some bollocks and gives him your number.
Dumb as a bag of hair.
You owe her nothing. If she’s still hiding from a potential spouse her history of being a lying, cheating, POS, then she is still a lying, cheating, POS, and hasn’t changed at all.
Glad her ex fiancé got the truth before the wedding.
I’m glad the fiancé left her when he knew how vile and disgusting she is and want you to know it’s good that you have shown her how
Consequences work
Just reading this, I can say for sure that your sister repulses me, too.
Your aunt is as bad as your sister is. If she is married, you might wonder whether your uncle knows she is probably a disgusting cheater, too.
Fuck the both of them.
Tell your aunt to fuck off and ask her who she cheated with?
But she didn’t, and still doesn’t care, given the lies she told.
I’m willing to bet auntie has a shady past and is projecting.
I wouldn’t forgive either.