One owner of a house wants to sell, the other refuses?

I own a house with my girlfriend. We jointly bought the property and are both on the lease. Things are not going well between us and I want to look into possible options if we decide to call it quits. I wouldn't want to continue living with her but she has already said she's not going to agree to sell the house. What are my options? If I just move out I'm still on the hook for the money, and I can't afford the house AND an apartment. I feel like she's trapping me in the situation.