My (28F) boyfriend (29M) found out I went to a party with college students while he was away for two weeks

I (28F) went to visit my boyfriend (29M) in the United States after a year of long distance. A month before I traveled he gave me an ultimatum, to break up or move there as soon as possible. I wasn't ready to do that so I broke up with him.<br><br>I was still in love with him even after we broke up and was jealous of the fact that he had moved on. I decided to go and visit him unannounced because he was the love of my life. Somewhere along the way, I realized I was making a huge mistake. I didn't have the money for the trip or the plane ticket and felt stupid for doing it at all.<br><br>He was shocked to see me at first, but he took me in and even let me stay with him (I was supposed to stay at an Airbnb but the owner backed out and I couldn't find another one). My boyfriend forgave me for hurting him. <br><br>During the time I stayed with him, he had to travel for work. He asked me to stay at his place while he was away for two weeks, but I didn't feel comfortable staying at his place with my stuff all over his apartment. I told him I didn't feel comfortable and asked if I could stay with someone else while he was away. He didn't seem to care much as long as I was fine, so I booked another Airbnb and moved out during the time he was away.<br><br>I met someone in the building where I was staying and he invited me to a party in the dorms. I didn't tell my boyfriend about it because I wasn't doing anything wrong and was afraid he would be jealous. I went to the party, got drunk, and returned. He came back and somehow found out that I didn't stay at the Airbnb. He went through my phone and emails and found out that I went to the party.<br><br>He broke up with me and said I was unfaithful because I was drinking with other men. He said I was lying and cheating and was mad that I didn't tell him. He said he feels betrayed because I was talking to other guys and that he can't trust me after this.<br><br>I don't think I did anything wrong. It was just a party and I didn'tsleep with anyone. I didn't even kiss anyone, just had some drinks and danced. I told him so, but he is still mad and doesn't want to see me. I don't know what to do to get him to understand. I feel like I'm being unfairly judged for something I didn't do. I thought as an adult he would be understanding but he seems to be really immature and petty about it. I don't know how to fix things.<br><br>What can I do to make him trust me and not feel betrayed? I honestly don't know what to do and want to fix it.<br><br>UPDATE: I apologize for the people who got confused about the details of our breakup and what made him travel. It's not anyone's fault but my own for not being clear. English is not my primary language. I said we broke up because he wanted me to move, but he actually wanted me to move a year ago. I decided to visit him after he started dating again. I'm sorry that my English is poor and I confused people. I'm going to work harder to be clearer. Thanks for the kind words and advice.