I totally get it. I had to schedule this test my Mom, and having the driving instructor, the doctor and the insurance agent say "No more driving." It finally took selling her car to get the point across, and she called me mean for the rest of her life - but after 2 strokes, her brain couldn't process anything that was to her left - like oncoming traffic at an intersection.

Every time she said "Why can't you be nicer, like your sister?" I said, "Why can't you be more reasonable, like your Dad? When he almost had an accident, he gave you his keys and said sell my car"? She would stick her tongue out at me like a little kid, and forget about it for a few days...
Ah, life. Was just talking to my close friend - my cousin, also her lifelong friend, is having memory issues and we're 1000 miles away. We're trying to decide how soon we need to call on her 4 kids (all near her) to get busy assessing what they need to do to help her.
Sue