My FIL should not drive anymore. Unfortunately, he's passed special examinations from the DMV - twice - and the last test was about a month ago. So he's sure he's a fine driver. Frankly, he has the legal backup to "prove" it. My MIL says if the DMV says he's OK, he's OK (but she's nervous). They have to make a long trip to a military base each month to pick up meds and do inexpensive shopping. These trips wear them out, so now I must go with them. Since it's on base, I can't simply run these errands for them. (My husband's slightly disabled, and there's no one else within hundreds of miles.) My FIL, of course, insists on driving - and on taking their car - and MIL backs him up. This is really getting scary, but I see no way out, and I resent being in this precarious position. Guess this is just a vent.
I would definitely talk to his dr, let them know that he passed DMV test but you are seeing slow reactions, poor judgement, and are concerned.
Also make sure someone from family talks to whomever prescribes his drugs and explain the predicament. That age group is proficient at editing info to make it seem like they "have" to do certain things. The dr may have more flexibility than your FIL is letting on.
Do not let him drive you. He might through a temper fit but sooner or later he's going to have to face up to the reality that a bruised ego is better than someone getting injured or worse.
Military pharmacies, however, are a thing unto themselves. But I've found hints that there may be some complicated mechanism to allow me to pick up meds. Getting on the base in the first place, however, is another issue.
The meds are the sticky point, and a big one. Between trips, they do shop locally. But he shouldn't be driving locally, either. For now, that's between FIL and MIL, who does drive (when he lets her). She also wisely limits her driving.
That Said ... I think I've come up with an argument for tomorrow's trip, and a possible workaround for future trips.
Will let you know about both, if they work.
Also, if these trips "wear them out" I do not see how bringing you along wears them out any less - maybe you are helping with the bags. If these trips are so hard on them, maybe they can consider an option closer to home. How much of a cost savings is this, after you factor in car expenses and time?
Sometimes people just want to hang out to familiar habits because that is the way it has always been done and it helps them hold on to their better (healthier) days.
As for the long term, if his license is finally taken away, then they'll have no choice but to let me drive. He's still too law-abiding to defy the DMV.
What I'm worried about in the even longer term is what happens if/when neither one can "supervise" me while we're on base.
As for now, I'm stuck. If his driving was the only issue, I wouldn't be doing this at all (though I'd still be/feel responsible if anything went wrong).