LoKe, I've had to deal with family violence, although admittedly it wasn't nearly so bad as yours.
A while back, I was just 18, and my father got really, really drunk at a party one night. So drunk he was driven home and literally had to be carried into the house because he couldn't stand up. My mother and brother were out of town, and we didn't know any of our neighbors. After a few hours, he sobered up enough to really, really, want to go back to his party. Now, we had one car there, so I had confiscated and hidden all his keys; he couldn't go anywhere, but I didn't want him to go outside, because he could have been hurt or could have hurt someone else. He started getting belligerent, pushing me and pulling me, and trying to get me out of the way. Eventually, he slapped me. I told him if he did it again, I'd call the cops. He did it again.
I stuck to my word.
It hurt, it hurt bad to have to call the police to arrest my own father because he was being a drunk asshole. He'd never been that drunk in his life, and after a night in the drunk tank and the DV charges (I didn't want to press, but VA is a must-press state for DV charges) he's never been that drunk again. To this day I still wonder if I made the right decision; he had to have anger management and see a therapist, I know he couldn't have hurt me, it damaged his record, but it was 4 AM and I'd been awake since 6 the previous day and crashing and he was full of energy and getting violent.
I guess I'm kind of rambling but my point is: no matter how much it hurts, sometimes you have to set them straight. Beating him is not a solution because you could cause damage, no matter how careful you are. Hoping he stops is not a solution, because it won't. Appeasement is not a solution.
If it ever gets to the point where you are in danger, you may have to call the police on him. Sometimes all it takes is one night in jail and dropped DV charges and they straighten out.