Had sex with a guy 4 days after breakup and need advice please

So a couple weeks ago I broke up with my boyfriend because I was having doubts about us. I felt disconnected from him and I was always getting annoyed and didn't feel a spark with him. I knew I loved him, but something was missing. I thought maybe a breakup would help us grow individually then if we were meant to be we would after we each changed for the better and found ourselves outside the relationship. After that I started getting upset about the breakup so I hung out with a friend who isn't the best influence. She would always want to go out and drink, so I did too, not wanting to be alone. One night I went out with her, drank a little too much, and ended up having sex with a guy. I regretted it from the moment it happened and told my ex the next morning what had happened. I wanted to be up front and honest and I feel terrible and don't want to lose him. Ever sense then he has been treating me like the worst person. I hate myself for it everyday. I regret what I did and wish it never happened...with that being said He constantly calls me names and makes me feel worse than I already do. I know he's hurt and angry because we did date for almost 3 years. Do you think he will ever move past it? Do you think I'm worth forgiving? It's so hard because i know I'm the messed up person in this situation...but I can't imagine my life without him. I made one mistake, I just want to know outside opinions about if I should keep trying even though he's treating me like shit and calling me unforgivable things, or if what I did is too much for someone to forgive and move past. I don't think this one mistake defines me as a person but I also hate myself for what happens. Please any advice or experiences will help. Thank you