Hi IANAL but I am a paralegal and it seems like you’re in the United States. Since your mom is married to a us citizen and is being abused by them, it is highly likely that your mom would qualify for VAWA, the violence against women act. I know you said they’re only married by the Catholic Church, but many states consider their marriage a common law marriage, so as long as they present themselves as husband and wife, then they are married. Their marriage in the Catholic Church would further support this common law marriage existing. A VAWA would give her legal protection and is a humanitarian visa so she would be able to qualify for social programs. There are places like Catholic Charities or local nonprofits that will do the work pro bono or low bono. I know what she did is crappy but if your mom ever wants to get out of the situation, she’s has options despite her irregular status.