What are my options for enforcing separation agreement when spouse claims he cannot afford to refinance?

My husband and I signed a separation agreement stating I will refinance the house and he will refinance the boat within 90 days of signing. I am in the process of trying to assume the mortgage but was told by the bank that him not refinancing the boat puts a strain on my debt-to-income ratio and may cause problems with my ability to qualify for assumption of the mortgage. My husband has not refinanced the boat because the bank will not allow him to finance it longer than 48 months, which would double the payments on it. He says he can't afford it, but he lives at home with his parents, has a steady income and no debt. He has been staying at motels with women, wining and dining them, and drinking non-stop since we separated so there is no excuse that he can't afford it .