Why would you want to file separate tax returns just because she is receiving SS payments?
All her benefits would be taxable if you file as Married Filing Separately.
Up to 85% of Social Security Retirement/Disability/Survivors benefits becomes taxable when all your other income plus 1/2 your social security reaches:
Married Filing Jointly - $32,000
Single or Head of Household - $25,000
Married Filing Separately - 0
