You are in a very messy legal situation as you are in a position that is impossible to achieve in theory .
If your name is the only one on the deeds then you are the owner.
If his is the only name on the mortgage - well it can't be. You can't have a mortgage on a property you don't own.
If that's really the case someone has messed up big time on the paperwork - you could sell the house, pocket the money and leave him saddled with the debt.
If you are saying there are two names on the mortgage that's more feasible - you as owner can still sell without his permission but will have to repay the whole mortgage.
Poor sod.