I know we all have so many problems that this one seems small. My husband had to quit driving a yr and a half ago because he got lost a couple of times and the kids were worried about everything about his driving. I rode with him daily and I didn't have a problem with it. But anyway the dr said it was time for him to quit driving. So I drive. He is such a back seat driver that he makes me a nervous wreck and mad as h*ll too. He tells me which lane to get in and when, where to turn, when to stop for a red light, when to go etc and he is so ugly about it like I don't have any sense. He hasn't always been this way, it has just started the last 3 months.. Today he made me so mad that 2 times I pulled off the road and stopped the car and said you drive. He refused so we just sat there. I am not a bad driver and I do the best I can. He told me I should try to get better. I'm 70. I told him today I wasn't going to let him ride with me anymore but of course I am because I can't leave him at home alone .Although I would like to do that for about 30 minutes to see if it would scare him and make him treat me better. I know I can't change his behavior so how do I learn to let it just roll off of me? I know this problem is insignificant compared to some of the problems we have but my whole life revolves around taking care of him.
Hang in there!
Lots of men are like you husband, can't stand to not be in control and hyper critical if you don't drive exactly like he would. I find it best to ignore the nagavating about 90% of the time but my wife does not have dementia. That makes it very hard for you to reason with him. You mentioned that this has gotten worse recently . It could be that the dementia is progressing.
I don't have any easy answer for you. Leave him home if you can. You may have to find a respite caregiver if he can't be left alone. You need to be able to get out and drive without the drama, and to Just get a break from him.
"You DO know you really hurt my feelings when you criticize my driving...I'm beginning to wonder if either ONE of us should be behind the wheel."