Sounds awful
I have to echo what has been suggested and say no more family visits, for awhile. That doesn't mean ever, I'd suggest just missing a few then go back and see if her attitude has changed any and if it hasn't review it again. It sounds dreadful and it is not something I would do, put up with.
My mother does it with my younger sisters two kids. She spends 4 hours on public transport taking her kids to see my sister. My sisters not in a rehab though, just doesn't live at home. It's awful that she won't go see her own kids but then at the same time since she can count on my mum to arranging it all, she's got no incentive to, has she?
A wise man once said, "Nothing changes when nothing changes."