AITA for not liking my brothers wife
This is my first time posting sorry if the format is weird I also don't have the best grammar I was homeschooled lol
Me 19f my brother 29m my brothers wife 27f
Okay so back in 2022 after they got married in 2021 she cheated on him he got really mad at her but she convinced him to have an "open relationship" but he doesn't sleep with anyone else. after that I didn't talk to her or see her for two years nor did the rest of my family till she got pregnant with a baby girl in 2024. then she somehow just started talking to my family like nothing had happened I didn't want to talk to her because she had cheated on my brother and was very manipulative to him but my parents told me to just suck it up and talk to her so I can have a relationship with my niece so I did I talked to her like nothing happened so when my niece was born I could see her
Fast forward to 2025 when my niece was born I was talking to her and my brother like nothing happened still because I was too scared of causing drama but I started to notice my niece looked nothing like my brother or his wife but I didn't say anything and kept it to myself
Fast forward to last week I couldn't stand talking to her like every thing was fine so I had a peaceful conversation with my brother and his wife about the fact that I couldn't get over what had happened they told me I was being dramatic and it happens sometimes people cheat and get back together all the time and it's in the past I tried to tell them that I didn't like talking to her knowing that my niece could maybe not be my brothers (I didn't try to say it in a mean way sense they technically have an open relationship I didn't think it really mattered) they didn't say much after that they didn't seem mad so I went home and told my parents about it they also seemed fine with it so I went about the rest of my week like normal
Now yesterday my brother was telling my parents that I talked bad about his wife and I'm an awful person and if I don't apologize he will cut me off and go no contact he also texted me saying he's giving me three days to apologize or I'll never see him or my niece again I asked him what exactly I said that made him or his wife mad and he said I called his wife a narcissist (which I never did) and disrespected his marriage I didn't think I really did but I'm starting to think I was too harsh and I was being an asshole so AITA for confronting them
Update: so apparently my brother was having a mental breakdown because when I said it could maybe not be his kid last week he actually got paternity test and it came back as not his kid and he didn't know what to do. So he was mad at me for talking to him about it because "he would have rather been delusional but now he wants a divorce" I told him I was sorry and I shouldn't have said that, he said "it's okay but now I have to get a divorce because she told me she wasn't cheating anymore and it's kind of your fault" he was very upset
But now I feel even more bad about what I said to him I apologized multiple times but now it's my fault he wants a divorce
I don't know if he will go through with the divorce or not he is an emotional wreck right now so I won't be talking to him about the divorce or anything unless he comes to me about it because I don't want to hurt him more than he already is
Also the reason I'm saying he had a mental breakdown is because that is why he told my parents that "I disrespected his marriage" and that's why he told me he would cut me off because he didn't know what to do and he was freaking out
So I've kinda come to the conclusion I am the asshole but tell me what you think