AITA For telling my mom my dad cheated on her and not blaming it on someone else

My parents were married for 22 years. My dad cheated on my mom three times. The first time he was able to convince her that it didn’t happen and that the woman involved was lying. The second time my parents got a divorce that only lasted a year. The third time was when I was around 16 or 17. <br><br>I still remember the first time my dad cheated because he was in such a panic. I remember he had to tell his mistress that the affair was over because i had figured out that he was cheating. He tried to sit me down and talk to me about it but I didn’t want to listen. I knew what he had done and that’s all I needed to know. <br><br>When i was 16 and my parents were married again, my dad had an affair again with the same woman. I remember my mom coming to me in tears asking if I knew anything and if I would tell her the truth. She had figured out he was cheating again and needed to know who. I told her the truth. I told her his affair partner’s name. <br><br>My parents got a divorce and my dad hates me for ruining his life. He told me years later that if i had just lied to my mom and told her that his mistress was a random woman at the bar then she would have been hurt for a while but she would have stayed with him. He said i was disloyal to the family. i don’t think so. <br><br>I saw my mom cry over his cheating. I saw my dad tell me i was disloyal for telling my mom that he cheated? No, Fuck that. She deserved better than that.