If you can run away without your parents using police to force your return, that's the simplest route. Your other relatives may get in trouble if they give you shelter without notifying your parents, so even a small amount of parental cooperation would make things way easier.

Your state's department of child services may be able to remove you from your current situation and possibly even place you with your other relatives, depending on your living situation. There's a whole investigation involved if you go this route.

Emancipation may be a possibility. It looks like your other relatives can actually petition for it, but it looks unlikely to be accepted unless a parent agrees to it. With an abusive situation it may be possible regardless.

I'm very sorry you're in a situation like this and I hope you find a better one soon