My mother is getting out of control, how can we stop her before she does more harm than good?

My mother (who is 90) has been getting progressively worse. Most of the behaviour stems from loneliness and we suspect some memory loss too. She drives around going to various family members (my wife's family) homes unannounced or just doing a 'drive-by'. She has mentioned several times that she has gotten lost going to places she has been before. She calls at all hours of the night claiming panic-attacks. On one occasion she called the police to check on us when we didn't answer the phone (we were at the movies). Most recently, she called my work and told the receptionist she wanted to know if I was there and OK, since I was at a party the night before (I am 64 years old I was not at a party). She told the receptionist not to tell me she called. We have POA, but what does that really mean? Can we force her to sell her home and move to a more suitable place? Can we have her license revoked? Since she has cataract and shouldn't be driving. Her home is falling down around her and she doesn't have the finances for upkeep. She keeps insisting she wants a roommate. We have become more concerned about her decision-making since she makes friends with strangers and we question their motives and the sitaution she places herself in. My wife and I still work full-time. We help our daughter with day care after we get home from work. Both my wife's mother and mine are both living so we have to divide our remaining time between them. What I can give is not good enough for my mother and she is starting to create problems for us and our extended family (ex. she called my daughter's husband at work to see if he was there. She calls my wife's 93 old mother asking if she will call our house. She calls my wife's sister to vent). What can we do?