Recapture of Federal Mortgage Subsidy

I was the only one on the mortgage and the MCC (Mortgage Credit Certificate) because I bought the house when single but I got married and then filed jointly when receiving the mortgage interest credit in subsequent years. I sold the house last year (7 years and 3 months) after purchasing. When figuring out the Recapture Credit on form 8828 Do I use just my Adjusted Gross Income for line 15 or do I use both mine and my spouses since we are filing jointly? If I have to use both, would it be better to file married filing separately?