How mobile is she without a car? Does she need help with day to day stuff like cleaning and cooking? Can she take meds without supervision? If you can find an apartment or senior housing near an urban area near stores and parks, can/will she get out by herself, shop a little, go the park, have a life? One advantage to senior housing with individual housing units is that people can live along (independently) and still meet other seniors and have a regular social life with their peers.
If she is reasonably mobile but does not have a car, it is useful to have someone with a car meet with her several times a week to take her shopping and to appointments. Routine access to libraries or senior centers or shopping malls is also useful.

