Help on a really crazy mother!?

Talk to a councillor at school, they can help you with things like emergency accommodation etc I moved out at 17 for my own reasons, it is possible. Sorry but that's your only answer by the looks of things. How old are your brothers? Can you find some arrangement with them all move out together? Where I'm from you can get Austudy which is where the government will give you payments while you're at school so you can continue your education, you and your brothers would be eligible by the sounds of things. It's hard but possible and not as hard as staying around her by the sounds of it.