That's not appropriate for a therapist to say. But, I have to ask: who told you this? Did your boyfriend tell you that his therapist called you "Hitler-esque"? If so, it's possible he fabricated that in order to make you feel guilty. Remember: he betrayed you and refused to give you space when you asked him to. So, it's entirely possible he completely made that up -- and if he really did make that up to make you feel guilty, do you still want to be his girlfriend?

Even if he didn't make that up, don't you think your boyfriend may have fabricated his side of the story in order to make you look like a villain in the eyes of his therapist? I mean, if his therapist did call you Hitler, you can only imagine the kind of things he told her. So, don't you think he might tell other people the same thing? Do you want to be friends or partners with someone who does that to you behind your back?

Personally, I would break up with him. He sounds like a major a**hole -- but it's ultimately your choice.