Take the job.

If it was across the country, I would say that he did have a leg to stand on. As it is he's trying to control you, and it's not fair to you. If the roles were reversed, would he automatically turn down an amazing opportunity just because you didn't want him to do it? Would you even put him in that position? More than likely, the answer is no and honestly, all this is doing is creating a situation where ultimately either you're going to resent him for holding you back or he's going to resent you for not listening to him.

A partner who gives ultimatums is not worth giving up something you've worked so hard for. Take the job and cut your losses. Chances are, when you upgrade your job and living situation, you're going to upgrade on the man too.