How to decide if family member with cognitive decline can be allowed to stay in home, living alone.

I am writing for advice about my sister who has been diagnosed with dementia that is vascular related, not Alzheimers. For the last five years, her declining decision making and ability to engage in executive functions, such as managing medications or finances, has become evident to me, her health care provider, and her friends and neighbor's. She has been admitted to the hospital several times when neighbors have called the police about her erratic and confused behavior. I have, after these many years, had her admitted to a residential facility. Actually, she is in the second facility within 12 months because she was removed from one facility for aggressive behaviors with another resident. She was also admitted to a psychiatric hospital two times, the last time as a result of her aggression. She is capable of self care such as bathing and dressing. She doesn’t cook and when she was removed from her house, her fridge was filled with spoiled food. She also drank heavily and did not take prescribed meds. She did work outside in her garden. Her driver’s license was revoked by the state because of her diagnosis being reported to state by her neurologist. She has clear physiological changes in her brain which indicate severe loss of executive reasoning. She is very angry and is able to write texts and emails using a cell phone which she also uses to call friends. Sometimes at all hours. She is very angry and begs to go to her home. She owns a beautiful home in a beautiful community y of people who care about her but are worn out by having to deal with her cognitive decline and behaviors. She is begging to go home and sends me 30 emails a day saying I’m trying to kill her. I live 500 miles away. I am 82’ years old and my husband is 85. I am wondering if there is any rational reason to think she could go back to her house with help. She has refused help or meals from services in the past. I am so saddened by this situation and wondering if I need to find a way to send her back to her house. As I write this, i wonder why I can’t accept she can’t go home. But I feel guilty about not finding a way to do that. What do I do here?