My guess is that he feels he doesn't have enough control or something, and by doing something he knows you don't like (and not actually going through with it, because he's not actually interested) he feels independent or in control or something.
I think if that's the case it's BS. Only a bully needs to hurt others to feel validated. If he has issues where he feels out of control or trapped or whatever, he needs to address them with you, not punish you.
Ultimately you might have to see a counselor or something, but in the meantime maybe talking about it will help?