<human>: Summarize the given text in a few sentences.

So I've been dating this girl for a few months now, we had a thing a few years ago but decided it wasn't the right time. We've been dating again for 3 months, she has been my best friend for years and I don't know what to do. I got out of a relationship because my ex cheated on me with my friend and it's left me with trust issues I guess. Now don't get me wrong I trust her, it's just some of the guys she's friends with. So her prom is in a few months and she's bringing this guy who raises a few flags with me. He tried breaking me and my last girlfriend up and there is no question, he will be her prom date. And to be honest I'm okay with it, but she wants me to go aswell. I just don't think I can handle sitting there watching his have his arm around my girlfriend knowing that he is inlove with her. She's mad because I don't want to go and watch that and at this point I really don't know what to do. I don't want to lose her but when we talked about it last night, she was really mad. We're having a talk in a few hours when she is off, but I don't know what to say! Help!
<bot>: Girlfriend has a friend who raises flags with me and she's taking him to prom and I have to sit and watch it