Former NFL QB Erik Kramer wants to erase his marriage from the books ... claiming his 2015 failed suicide attempt left him with a lack of mental capacity to legally consent to marriage.
According to new legal docs ... Kramer says his wife Courtney Baird stole $50k of his money before they wed, and she's now filed for divorce.
He says before they got married, Baird "exerted undue influence upon me to convince me, given my weakened mental state, that her actions were not wrongful."
Now Kramer claims his 2017 marriage -- which lasted less than a year and a half -- never should have happened in the first place .