[GoMangoMan]

I'm sorry that you are going through this. My aunt suffered with this when she was in her mid-70's. My cousin didn't want to take the car keys away until my Aunt became disoriented and lost in her own small town. Luckily she was driving past my parents house several times and my Mom (her own sister) flagged her down. Although she didn't recognize my Mom, she pulled over and parked until my cousin could come over to get her home safely.
Jay and LoBelly have offered excellent advice. Good luck to you.