You should probably go to a local CPA or Tax Accountant to straighten this out. You needed to file as Married filing Separate. Did the tax preparer know you were married? You might have been able to file as Head of Household if you didn't live with your spouse the last 6 months of the year. And you might have been able to file a Married Joint return with an injured or innocent spouse form to protect your part of the refund.
