I'm being abused by my boyfriend and mother at the same time?

I lived with him and he threw me out after a few months of tension arguing and passive aggressive behavior. My only option was to go back to my mother's house. One night we were fighting and before he knew it he had his hands around my neck choking me (he was angry because I was out with my best friend and he thought I was with other men and accused me of clubbing and drinking at noon). It never got explained, he just promised he would never do it again. The first time I tried to end it with him he turned into a scary pile of tears. He has also threatened suicide following many arguments. He recently forgot my birthday and when I confronted him at which point I had gotten drunk and hysterical, he called 911 on me to "get me a cab" and had me arrested for domestic assault and battery. I now have a criminal record, when I never so much as have gotten a parking citation. In police custody I sustained some serious injuries because of my state, I was completely blacked out and tried to climb up on the sink in my cell and fell on my face. I have to lie to my mother, friends and family to maintain this secret, because they are not capable of emotionally supporting me. My mother is quite unstable and I cannot trust her enough to share simple day-to day happenings without her becoming angry, hysterical and enraged. Even though I am in graduate school, my mother constantly undermines my education and intelligence, whereas it seems like this is exactly what intimidates my boyfriend. He is only educated up to the High School level. My life seems to be falling apart so rapidly. My boyfriend or whatever he is is so engrossed in "his guilt" about what happened to me its like he wont let me heal, and expects me to be there for him instead of the other way around. He says he just wanted to get me home safely, I think he wanted to see me punished because he felt like I was "out of control" for being upset that he forgot my birthday. What do I do? I feel so damned in every direction..