Obviously the money came from Son's desire not to screw over his mother and grandmother - they borrowed it from DIL's family, they cut out Netflix and coffee, they've decided to live on beans and rice for the duration, they took out a home equity line, DIL has a sideline in phone sex, idk - and rather than sharing the guilttripping around, they were discreet about it.

Yes, this was exactly my thought! Where did the money come from? They struggled, you asshole, because they can't or won't make the commitment you need but they're worried about Nana and about you.

Also, not for nothing, but Gramma's insistence that you not hire strangers is abusing you, LW. It might not be intended as abuse; it might be the natural terror of aging in a society that's not great for support. But the result is abusive of you. Carolyn is right: "You can make your mom’s problems your problems, if you want."