So I’ll keep it short. Yesterday my girlfriend and her god sister went out to walk in a nice area during the evening around 6pm. We had plans to meet up at my place at around 10pm so she and her mom who has a car could help me with packing. As time flew by I called her around 10pm and she said that her mom allowed her to stay at this place until 00 with her god sister. After time passing I got this gut wrenching feeling in my chest that something wasn’t right and in the past few weeks she has been acting a bit different. I’ll admit I’m not a saint I have said stuff and did stuff I still regret to this day, but I have never thought or have cheated on her for context. So I grabbed a taxi and knowing where she was through Find Me app on my phone I drove by her location. Turning out she was with a group of guys who were by her saying around 16. For more context I’m 23 and she is 19. So it was her, god sister and like 4-6 guys and they were drinking so much that by the end of the night she was piss drunk. So due to seeing all this and the lies sinking in I called her up called her some names and cried. After that she did call me telling me that she hasn’t cheated also this is already around 11pm. I did reach out to her mom and we got taken back to her/ her mom’s place. Where she was apologizing for a bit then screamed that I was wrong the apologizing again. After this before going home I checked her phone which it turned out she added them on messenger and was already planning to meet up with them tomorrow which is today. So I have give her an ultimatum. Either have your friends or me. So far she didn’t decide but I have been up all night contemplating how could she even think about something like this when we have been together nearly 2 years. To pick random strangers over her own boyfriend. Apologize didn’t think typing this out would make so much easier on my chest yet long. So am I the ah or was I right to react like this in the end. Edit: I would have not gone there if I didn’t have the strongest gut feeling in the world that is like this. I tried to trust her but in my past I have head small relationships that didn’t last long due to my partners cheating on me. Due to that I can’t trust anyone fully not even myself sometimes.