Oh, love! I'm so sorry.

That sounds absolutely terrible. Big hugs!!
I was in a similar situation about a year ago. I had been with my first (and so far, only) boyfriend for a year and a half, and things went downhill the last six months of our relationship. He told me I was "too fat" and wasn't attracted to me anymore (granted, I jumped from 267 to 323 while I was with him, but I was still pretty heavy when he thought I was "beautiful"). Those last six months, sex was all about him getting off--he told me he didn't even want to look at me. He, too, was violent and had issues dealing with anger/rage. Looking back at all of this now, I can't believe I stayed as long as I did! I convinced myself he was stressed from school and once he graduated he would go back to the amazing guy he was in the beginning. WRONG! Still, I tried my hardest to stay with him and begged not to break up, because I still felt like I loved and cared about him and wanted to be with him. (I can't even believe I'm saying this now! XD) The final straw was him cheating on me with my roommate/"friend," and I finally ended it.
Losing a first love is HARD. SOOO hard! Definitely some of the worst emotional pain I've experienced in my near-21 years of existence. But guess what? It gets better. Everyone will tell you this, because it DOES!
For me, I didn't feel like I was out of love with my ex until after I cut him completely out of my life (blocking him on Facebook, ceasing all communication, deleting e-mails/texts, etc), which took about about 4 months. It was a slow process for a few reasons, but mainly because I was reluctant to come to terms with the fact that he didn't love me anymore. Once I got over that, I was able to move on more quickly.
Eventually I realized that time, surrounding yourself with people who love you unconditionally, and focusing on bettering yourself make the process a
lot easier to handle. As others have mentioned, though, it sounds like seeing someone would help, especially with your more traumatic circumstances. (I have depression and have had therapists before, and it helped me.)
As far as the food/eating habits go, well...surprisingly, after I broke up with my ex I
lost weight, which NEVER happens! (I have used food to cope with stress/emotional problems since I was 9.) I was at my heaviest and determined to make positive changes, so I decided to focus on bettering myself--e.g., losing weight. Yes, I was sad most of the time, yes, I had my off days, but I kept chugging along. I saw people and did things I knew would make me feel better; I did anything I could to avoid binging. I also stopped buying the things I knew I would go out of control with, like chips and ice cream.
Keep hanging in there. You deserve the best and he was NOT right for you at all! Start letting go. It hurts a lot at first, but it trust me, it gets better. <3