I just saw this thread, and I must say, this is a textbook case of abuse. Really, you need to do something about it. Call someone, whether it’s Shalom task force, the police, or a Rav that you trust. Even if only so there’s a record of it in case God forbid things get worse – it’s better if you can prove things were going on already.
His being super-sweet after is typical of abusers. They try to make up for it. The same goes for your feelings of guilt – it happens very often. I understand if you’re hesitant, and if it were only you, I’d be more sympathetic. But please, for the sake of your children, do something! Don’t subject them to this. It will mess them up for life. Get help NOW.