He hit you. I can't abide by that.. If you need help getting away from him, it is there. Unless you came at him with a knife violence is not acceptable. AT ALL. If he was a good person at some point, he isn't right now. He may need help, he may just be an ass... but either way, remove yourself from this. I don't know you but i seriously doubt you should have been hit for any reason. well, unless you attacked him with a knife :p
Know you have friends here, and everywhere. Reach out and take care of yourself. For me he is on his own to work out why he did it, and that has nothing to do with you.