Personally I found not responding to verbal abuse helps. After all they want a rise out you to hit back. Expect it to get worst when they realise they can get it out of you they go else where.
If they hit you fecking hit them back. Go for the nose hurts like feck. Then hit the throat they will down after that. Over wise kick the fecker in the nuts and then knee him in the face.
Never hit first that way you can claim reasonable force.
A bully will bully because they have problems and can't deal with them. If you need respond to their abuse use this against them. They will not think twice at using you weakness and they don't like hearing theirs.
Hope this ends soon for you.
I'll add something later on.