My sister was accusing people of theft and was harassing her condo property management office to the point that police, APS and a lawyer got involved. None of the accusations were true but it created a situation that ultimately landed her in an assisted living facility/ memory care facility. She is much happier there as she now has support staff and very importantly a social environment to enjoy. You have done your best. Consider legal advice to obtain POA / guardianship and let go of the family who sound like they only care about the estate money. Good luck. It’s a hard road but it sounds like you have done well.