I guess in looking more for just understanding from others here if anything. I doubt there's much advice or anything I haven't already heard...
My mother and I have been caring for both my grandmother for roughly the past 10 years or so.
In that time if went from small potential memory issues and minor assistance to outright demands, accusations, and harassment. I can't even remember the full progression of each stage anymore, just how many times what she's said was proven to be a lie or a false accusation of some form or another. (Example: accusing me of hitting her when it was a gentle tap on the shoulder, or shoving her when I'm more than 10ft across the room.)
She's upped the ante to now creating big fights, in public or in some similar format, while playing the poor innocent one and my mother and I get blamed for things.
It doesn't matter to anyone else that she purposely keeps us awake all night nearly every night, or that she's verbally harassed us and yelled at us.
Just that we're at fault for the noise she makes at night and that we yelled back. (Partly due to her claiming she can't hear us otherwise...)
We've had police be called out a few times now. There is also a social worker assigned to this and is aware of what she's doing generally, but so far has been unable to do anything to help.
We can't leave, we can't keep her away, no one else will help us, and we can't afford paid assistance. We're all drained and physically sick each day because of her. Yet we're still blamed for it all.... Almost never her....