Can you make him do what you want him to do? Can someone make you do what you don't want to do? Think about that, then ponder this . . .
How do you want to live your life - not "if my husband would behave like this I'd . . ." but how do you want to live your life?
You told him you were "tired of being threatened and weren't going to take it any more". What does that mean? Sounded like you were threatening him with something, what is it and are you willing to carry through with it? In my opinion, the "watching his P's and Q's" is only a temporary situation. What will you do when it ends?