AITAH for breaking up with my ex for cheating
(was an aitah post but didn't wanna reformat it)
I genuinely felt guilty so please bare with me. The initial incident happened about a year ago. It took some time for me to write this. My ex (22F) and I (22F to keep it simple) had been in a relationship for 4 years. We'll call her Annah. She had asked in the beginning if I was fine with polyamory and I agreed to try it. We of course laid some ground rules, boundaries. The main thing I wasn't comfortable with as a lesbian was her having intercourse with men and visible hickey's. She said it wouldn't be an issue for her as she was terrified of getting pregnant.
Fastforward a little and she is now dating 4 or 5 guys and I am the only one with female anatomy. I ask her about it and she says she's just pickier when it comes to women. I let it slide. But about 2 years into the relationship I had to move from the area for school and i was working at the same time. It was only an hour and thirty minute drive, but after doing that every weekend it can take a toll. So after about a year of that I cut back cause I could feel the tiredness in my bones, but we would still talk on the phone or play games together. And I would still visit her irl, just not as often.
Now we're to last year. I start to notice a pattern where she'd say she was going to spend time with someone and would go silent for hours. Her own mother couldn't get in contact with her, let alone me. And every time she would be with one of her other male partners. Her excuse was always that her phone died and she only just got a charger for it. It never made sense to me how it seemed to happen almost every time she was out with a male partner. She also felt like she was distancing herself from me. She suddenly didn't want to hangout on the phone anymore or play games together. I would stream anime or kdramas for us to watch and she stopped wanting to do that too. Those were my first red flags for what might have been happening behind the scenes.
We stopped spending as much time together, and it's not like she could just visit me some instead because she didn't have a car. Annah and one of her partners that now lives closest to her started spending more time together. We'll call him Keris. I had considered him a friend and we all watched chainsawman as it released together. The biggest turning point that I think I remember is when the movie 'Sinners' came out. I think it was the longest time she ever went silent while out with someone. Even her mother was worried. Upwards of 5 or 6 hours, no contact with anybody.
I never confronted her because I wanted to believe that she wouldn't cheat on someone since she had been cheated on before and how much she said she hated it. She told me countless times that polyamory was about open communication. How even in a poly relationship if you don't communicate your intent, it was still cheating. She would constantly talk about the bad rep Bisexual people had and how she wanted to change that, but instead did the opposite. That night I cried my eyes out, but didn't break up with her because I had no proof. I didn't want to accuse her and be wrong, so I waited.
Around June of 2025 is when I found out. She hadnt been feeling good and went to the doctor with her mom. The doctor told her she was pregnant. That night is when she called me to tell me. I was on discord watching demon slayer with my mom cause she wanted to catch up. She texted me and asked if we could talk. Me being willfully ignorant and naive assumed we would finally get to spend some time together. So we called and she said to me, verbatim, that she's pregnant and she thinks it's from hugging Keris too much. A grown adult tried to convince me that he had semen on his pants and because they hugged too tightly it got her pregnant (her explanation).
I bawled my eyes out having conformation of her cheating and hung up. I couldn't believe either of them would do that to me. The next day I confronted Keris and he said Annah told him I was ok with it. And so I asked why he didn't confirm that with me and he had no explanation for it. Throughout the process of me interrogating both of them Annah was mostly unresponsive. She would text but not really answer any of my questions or show screenshots of their chats. Keris on the other hand was a lot more open to communication since he was apparently lied to.
He sent me screenshots of her talking about how great "it" was in his car after seeing the movie Sinners. I knew it. But to speed things up she called me a traitor for saying I wanted to break up with her. When I confronted her with the prior evidence from Keris she said it was because of dissociative identity disorder (she is not diagnosed) and said it was an alter (alternate personality) that slept with him four times not her. She then started saying how it's not cheating if you're in a poly relationship even though she was the one teaching me about poly relationships and had said in the beginning that it was cheating.
I'm confused and betrayed. I didn't want to write a whole book so I didn't include everything she did to me through the four years, but i probably never should have let it go on for so long. She said I betrayed her and made her rethink our relationship by breaking up with her. What did I do wrong? Am I the asshole?
(i'd be willing to give more detail on what I went through in an update if it's wanted but only in bullet form of everything I looked past or previously forgave)
TL;DR: gf cheated and got pregnant by close mutual, thinks im a piece of shit for dumping her