What would be best, would be to file jointly and request Injured Spouse Relief:
This will allow you to receive your portion of the joint refund. His will be taken. You can also file seperately, but you will both lose the opportunity to itemize, take the EIC, and other things. It is never a good way to file if you can avoid it, but they made it that way so people could not pick and choose income, deductions, and credits between spouses.
You can file as married filing separately to protect your portion of the refund, or you can file jointly and make an injured spouse claim. If either way yields roughly the same result, choose to file separately.
Any individual seeking legal advice for their own situation should retain their own legal counsel as this response provides information that is general in nature and not specific to any person's unique situation. Circular 230 Disclaimer - Advice given in this response cannot be used to eliminate penalties with the IRS or any other governmental agency.