AITA for leaving my fiancé after receiving pictures of him cheating on me at his bachelor party?

Hi Reddit. I’m a 28-year-old woman, and I’m in a pretty messed up situation that I need help sorting through. A little background: I was planning my wedding to my fiancé, Jake, who is 30. We’ve been together for four years, and I honestly thought we had a great relationship. His bachelor party was last weekend, and it was something we had both discussed and agreed upon — he was going to Vegas with his friends for a few days, and I was totally on board with it. Fast forward to Saturday night. I was at home, binge-watching my favorite show, when I received a message on my phone that made my heart drop. It was from Jake’s best friend, Mike. We’re all friendly, so I didn’t think much of it at first. But when I opened the message, my heart sank further: it was a series of pictures showing Jake with another woman, obviously holding her waist and laughing together at a club. The caption read, “Thought you’d want to see what your fiancé is up to. Not cool, man.” I was in shock. I felt like the ground had been pulled out from under me. I immediately called Mike, and he explained that he didn’t want to be a part of Jake’s betrayal and thought I should know. He told me that this wasn’t a one-time thing and that they had seen Jake getting pretty close with this woman throughout the night. The next few hours were a blur. I went through a wave of emotions — anger, heartbreak, and disbelief. I couldn’t understand how someone that I thought I knew so well could do this to me. I finally decided that I had enough and I went to my parents' house to process everything. The next day, I called Jake. When he finally picked up, he sounded cheerful, like nothing was wrong. I confronted him directly and asked about the pictures. He went silent. Eventually, he tried to brush it off, saying it was harmless fun and that I was overreacting. That just fueled my anger even more. I told him I couldn’t continue the relationship, and he panicked, begging me to reconsider. I stayed firm, though. I have always believed in healthy boundaries and trust in a relationship, and what he did shattered that completely. I packed my things and told Jake it was over. I wish I could say I felt better after but honestly, it was heartbreaking. Now I’m back home, trying to put my life back together. My friends are supportive, but I can’t shake the feeling that I’m making a mistake by leaving him.AITA for ending our engagement after finding out about the cheating?