boyfriend problems...?

So to start from the beginning, me and this guy have been serious been dating for a while and according to him "were not allowed to break up ever" he's so good to me and all. I didn't go to hoco bc he didn't want me going so I didn't. That night he was supposed to call me(he's at college) but I saw in snapchat that he was drunk at a party and one of his videos he said "oh shit there was this girl with a fat ass I'm gonna go get her number" I ignored him and texted him back "wrong number go text the girl with the fat ass" I finally called him only to tell him that we shouldn't be doing this anymore, broke up w him, and hung up right away. I like him too much but all my friends are saying he deserves it. I didn't really ask him about it other than that so idk what actually happened. I miss him but I don't wanna be the one going back since he should be sorry not me. I really don't know what to do please give me advice..😩