I can imagine it would feel like a catch-22.

What about individual therapy for you then, for your feelings about the relationship.
It might even help him see that therapy is a positive and helpful experience.

It is a lot to have going on--grad school, moving, a relationship. Maybe you don't have to make a decision right now about the relationship. You've told him that you aren't sure this is going to work when you begin grad school.
If he goes with you when you move for grad school, then it is with the expressed understanding that you may re-evaluate the relationship and you may decide to not continue it. This expressed understanding, a result of an unhurried discussion, will include what you will expect of him if you choose to not continue the relationship--such as him being prepared to move out in a specific time frame.
This way, you will be giving yourself options that you will have every right to elect to choose.