My Mom will be leaving a rehab center next week. She wants to return to her own apartment. She is 87 and has had medical issues for the past 6 month

She was independant before September 2012. She has lived alone in a one bedroom ground apartment for the past 8 years. Her greatest wish is to return to her own space with her own familar surroundings. Rehab has suggested she not go home but live with someone. She is very unhappy and says she wants to spend what time she has left on this earth in her place where she feels safe. My sister is concerned that if something happens while Mom is alone we will be legally charged with neglect. Is this true? My Mom has started to suffer mild dementia but nothing requiring either my sister or myself to take over guardianship. I want my Mom to be happy but my sister insists we will get into legal trouble if we let her go home alone. She has wonderful neighbors and I am trying to find someone to come in and check on her daily during the week since I work a full time job. Please give me your input.