Depressed. Sleepless. Confused

...where to start... well... the past few years of my life have not exactly been the greatest... i was caught cutting myself by my mom when i was 13. I stopped because she threatened to send me to a psych ward. I watched as my dads ex punched him in the face 4 times while holding my 2 year old half sister, after SHE cheated on him and was pregnant by another man. She kicked us out, and my dad lived in his parents garage. the custody arrangement is for me to be with my mom sunday evening through friday evening, and to be with my dad the rest of the time. My dad found a new girlfriend that he is now engaged to, but her ex husband just got out of jail 3 months ago for nearly beating her to death, she has 3 children ages 18, 10 and 11. We found out she was smoking crack with her heroin addict friend, and she claims to have quit. But now she drinks alot. My grandmother is schizophrenic and i watched as she slammed my mother against a stove when i was 6, she is now living in the same apartment complex as i do, and is still very unstable, my aunt and cousin live here too. My aunt is a alcoholic and i find myself dealing with their problems nearly every day aswell. My grandparents on my dads side are usually there for me, but i find them to sometimes use me for information on whats going on in my dads life. I'll be 16 in 3 weeks. I'll have my liscence i should be thrilled... but i find myself depressed. and this is now my 3rd day with only an hour of sleep. my mind is playing games with me. and my mom refuses to help me out at all. she is convinced it is a "stage" i'm going through. and ignores it all together. Can anyone help me? i dont know what to do at this point in my life... At one point i thought i could balance everything out ... but the problems grew so fast, i have lost control of everything. Sorry it was so long.