I just saw in another follow up post about your financial situation. Maybe you should call his bluff and just anchor down harder, letting him know that he made you a promise and this is breach of contract. (verbal).
Talk to an attorney.
Call his bluff and let him be the one to leave.
If you are there and he doesn’t want you it will put a cramp in his style and he will eventually have to leave to get what he wants.
You could live there until you figure out what to do financially.
Move into another bedroom and don’t have sex with him so he gets the “full picture of what you are doing.
Do not make any kind of payments.
Let him completely support you and you save your money during this time.
I know it is the opposite of what you want but sometime we have to stand up for ourselves and love ourselves enough to do the right thing by our self.

He needs a lesson in humility. I hope you are the woman to give it to him!!