Any suggestions for this? Delusional woman in late eighties.

Her primary caregiver takes care of everything, house, groceries, appts., etc. She has been told by all three of her physicians that at least half of her grandmother's ideas are delusional. I have witnessed. But when her caregiver explains the factual reality of a situation, she is called " so critical! ", "you have a temper!" , all of which is not true. The issue is an additional person to help at home. She uses these words to describe her caregiver. Most won't take the job. The ones that do leave after a week after seeing what's going on, that she is smart enough to manipulate people, but sadly her reality is very clouded. If she weren't cruel, it might be bearable.