HELP !!! Please read..I need advice.

I don’t even know where to start. But from as long as I can remember my mom has always been a very negative and mean person. She’s always verbally abusing me and sometimes she even puts her hands on me. She makes me feel as if I am not worth much and that nobody cares about me.When I was about 11 or 12 I even cut my arms because she really made me think that I was a “bad” child and that I should just punish myself. Now she goes out with men she’s met of blackpeoplemeet.com and leaves me at home without cooking and having any real food in the house . I am now 16 about to turn 17 in a few weeks and today seems as if it is my last straw I’m tired of getting hurt and feeling unworthy. I tried to tell school teachers , councilors , my neighborhoods, my step dad (he doesn’t live with us anymore)and even my grandma. No one has helped me to get out of this house. It seems like I’m going crazy and i cant take it anymore . It’s hard. I try to do my best in school , and join clubs and clean the house and do as I’m told but I feel like nobody cares about me and it’s really hurting me. Today I came on my period and m cramps are REALLY bad so I stayed home from school. I had an doctors appointment today at 8:30 am but I missed it because my mom didn’t come home till 9:40am from when she left last night because we got into an argument this may sound crazy but just because I asked her if I could take a shower in her bathroom since I saw a bug in mine. She cussed me out and said “fuck you and your birthday “ which made me mad since she ruins all my birthdays every year . Anyway so she gets home this morning and she’s mad that I’m at home so she’s screaming telling me to get put her house but my cramps are so bad I do nothing but lay here but I hear her yell “I could kill yo ass” it makes me so mad I get up out of my bed and bang on her bed room door so she could open it ,she opens the door and chokes me so I drab her arm from around my neck and dig my nails into her arm so she can let go after the altercation she notices that her arm is bleeding from when I tried to get her off me so she tells me she’s calling the police on me . What should i do? I can’t take this anymore (the picture is a screen shot of how she usually talks to me ) (btw in the only child and I don’t have any family where I stay) (i also think she’s an alcoholic)