How do I deal with my pathetic attempt of a mother?

So I am 15, turning 16 in 2 months, and I don’t know what to do about my pathetic attempt of a mother. Ever since her and my dad got divorced when I was 5, my life has been a living hell. She has had to worst boyfriends, all who have hit her by the way, and she trys to bring them into my life. I have come to accept that her and my dad are over and trust me I am perfectly ok with that. She has never been there for me. She has always criticised me and talk me down, and I am old enough now and I want to do something about it. A couple years ago I moved out from her house and stayed with a friend for a year, but then she became of age and moved out herself and into her boyfriends house, so I moved in with my moms best friend. I love it here. I always have. I was finally away from my mom until her last current boyfriend threw her out and she had no where else to go and had to move in here. Ever since I have hated my life and had thoughts of taking myself out. She drinks all the time. smokes constintly. yells at me for something I didnt do, or if she is mad and wants to yell. I cant do the things I use to. I hate it. When I say I hate my mother I really hate her. I know I hate her and I have that strong of hate towards her. Not to mention she is a sleezbag and sleeps around. She is a pathetic attempt of a mother. She has three beautiful daughters [2 of which are my sisters] and I am the youngest. I am just affraid that there is nothing to do about it until I turn 18. I would go to childrens services but I dont want to move out of here and lose every good thing that I have in my life. I just want away from her and despritly. All my friends agree with me about everything I have just said, but I want to know what I should do. I still have 2 years 3 months and 7 days [[[yes I am counting]]] till I turn 18 and I get out of here. but honestly I dont think I can wait that long. She is much worse than what I am writing, but I dont think I could write that much. I’m not afriad of her or anything. but I dont think I can take this my whole life. I grew up in bars because she loves to drink. its sad I know everyone there and I know a lot about drinks then I think any 15 year old should. What should I do? Any advice? Anything helps!!!