Oh sorry just read again, they were never married ... well as far as I see it they still both own all of the house together and are both liable for the mortgage. It would need to be decided as to who gets what percentage of the house if it were to be sold, or one would have to buy the other out. If he paid off the mortgage she would still be on the title of the house wouldn't she so it wouldn't make any difference .... they either have to agree what to do or go back to Court.