My sister still works full time and tries to get anyone she can to keep mother, including her husband who is at his wits end with it. I can't keep her either, she is so much to deal with. She is 96, dementia, blind and doesn't know anyone anymore or who she is. She is never content, and continually asks for things to be done for her. My sister is the fudiciary but do I have any legal right to make decision for her to go to nursing home?
Does Mother have an advance health directive? Often that document names the person who can make medical decisions when the person cannot make them herself.
Good luck!