@bigpoppacg4204.c if you are going to file joint and are worried that someone else will claim her (that is a form of identity theft as that someone else would have to know HER social security number), you can apply for a PIN which would preclude anyone else from efiling a return with her social security number on it. Only the person who knows the PIN (presumably only you) could efile. if the return is paper filed, the IRS is going to closely scrutinize the return because it was submitted without the PIN.
HOWEVER, if you file Separate, that is HER issue and not yours; and I personally would do nothing.
https://www.irs.gov/identity-theft-fraud-scams/get-an-identity-protection-pin
