My husband and I married March 2012. I was 20 he was 21. We were both students, but we attended separate universities. I worked, but his mother paid for all of HIS living expenses and for his college for more than 6 months out of that year. I was required to file taxes since I made over the 5,950 mark (barely), but because his mother claimed him as a dependent he apparently could not file married filing jointly which made me have to file married filing separately. Now I can't receive financial aid from my university because they're saying what his mother did was illegal and he has to send in at least some sort of tax transcript. BUT HE COULDN'T FILE TAXES! I feel like we're caught in this loop! Help!

Do you live together? Does he or both of you live at his parents? Dos you claim your school expenses and everything you could?

"You cannot claim a married person who files a joint return as a dependent unless that joint return is only a claim for refund and there would be no tax liability for either spouse on separate returns." YOU WORKED, so your income was combined with his zero income!
"The child must have lived with you more than half the year." DID HE??

What you and your husband should do is file jointly, and you attach a blank 1040X with a copy of the return you filed, with an X through it, just to make it clear that you are now filing jointly.

Let the IRS sort out his mother. What she did wasn't right if she didn't check with both of you!

His mother did NOTHING illegal, but she SHOULD have checked out all of the ramifications of her actions.

You can still fix it by filing jointly. Did you get a COMPLETE refund of the withheld taxes?

Her married son's option to file jointly supersedes her option to deduct him.
She can't do both because her daughter in law had a tax liability.

It is possible she had NO tax liability. That is why I asked.