Sounds like your mother is a social person who also needs her own time and space. We went through that with my mother when my father died a few years ago - my sister and her spouse remodeled their basement (ok, it needed it anyway) into a studio apartment apartment with a shared bathroom with the two teenaged girls. Too much company too much of the time. She ended up moving home to north Florida where she has all her "stuff". If your sister is at all like her, a room in somebody else's house would be a bad solution.

I'd agree that getting her to move into other digs, either closer to other family members or in Juneau would be a better solution. It also sounds to me like she is a prospect for a bad fall, living alone or not. I'd encourage her to check into the Lifeline System.