Sorry to hear, that is a mess.
I don't want to tell you to leave family, but i had similar issues when i was young, and so I left home(two weeks before my 17th birthday) and never looked back.
I do have family, but its mostly in laws and friends i consider family.
The point is, if its bad enough, something can always be done, and sometimes that means distancing yourself from certain people, even if they're family