Stressedmummy, I am so sorry you're in thie awful siutation. It's easy to say that you should leave, but if there is no obvious place for you to go, it's not that simple, I know.
I have a slightly similar situation at home, (see my thread below!), in that my main issue with DH is his inability to control his temper. He also had a screwed-up father, and as a child he regularly saw his parents hurling furniture at each other. But he swears he would never hurt me. He hasn't hit me or the children, but when he loses his rag, I do feel afraid of him now in a way I never did before.
I don't know what to suggest to you. I have managed to get DH to agree to some counselling, but as yet nothing's happened and I don't know how effective it'llbe anyway as i think he's only going to do it for me, rather than becasue he thinks he really has a problem.
If someone else thinks they're in the right, there is nothing you can do to change their minds, IME.
My personal plan is to give him every opportunity to show me he wants to change, and to carry on as "normally" as possible at home, whilst quietly making sure I am in position to leave quickly if I have to. I plan to see a solicitor in the new year, to find out exactly what my rights are and how we could keep it all as smooth as possible for the children. It would also hepl if I coudl stash some money away somewhere, but not sure how i'd manage this as there isn't a lot of the stuff going spare.
Anyway what I'm saying is, you must look after yourself and your children first. Perhaps pointing out to him how his behaviour affects the children (rather than you) might change his outlook? No normal man wants their own kids to be frightened of them, and if he can't control himself for their sake, then he really isn't worth the effort on your part. Thinking of you.