Narcissistic Mother and her Flying Monkey (POA); I don't know what to do.

During a weak moment, I moved in with my 95 year-old-mother. She was afraid of staying alone, as well as fear following my father's death. She appointed my brother, who is a disabled utility worker, her financial/medical POA. I am a retired registered nurse. This has been the absolute worse two-years of my life! They lie, steal and are master manipulators. I overheard one of their private conversations. My mother asked my brother if he had "everything." He responds: Yes. She then says: No matter what, even if she begs you, don't you give her anything, not even a dirty-penny: let her starve! Nope, no dementia... just plain vicious meanness.

I took care of my father. I cook daily, care for the home, do laundry, shop and drive her around like ms daisy. She has always treated me like the family scapegoat and because I loved my father, I just turned the other way. Her level of criticism, judgment and slights is staggering and, until recently, I hadn't realized how it has affected my health. Here we are in the middle of a pandemic and I am trapped in this house with her and daily visits from her flying monkey. I planned on moving to Arizona, but with this world-wide crisis, relocating to isolate would be impossible. I just don't know what to do. :(.