Dear Carolyn: My mother-in-law is on oxygen, is wobbly on her feet, can’t hear or see very well, and is understandably forgetful. She lives by herself and refuses to have anyone help her except me. She has three children (my husband and two siblings who live out of state), but I am the one who spends the most time with her and knows her condition the best.

I called her primary doctor to say my mother-in-law should not be driving. My husband and I have had several large fights over this. His response is when she gets in an accident, then he will have that discussion with her. He knows that is a bad plan.

I took her for her appointment, and the doctor did take away her driving privileges. The doctor asked me my opinion in front of my mother-in-law, and I said that although I don’t get a vote, I think she should not be driving. Needless to say, she is devastated, and furious at me.

My husband is mildly annoyed that I called the doctor and said it wasn’t my place.

So, now she is mad at me, still driving. My husband talked to her and said I did it because I love her. She said she would be careful driving, and he said okay. He refuses to tell her she shouldn’t be driving because he would then have to deal with it.

I have decided to stop mothering her. At lunch yesterday, I didn’t help her in and out of the car or give her my jacket when she was cold, and when her oxygen wasn’t on, I didn’t tell her. My husband said I was being rude. I said that I was treating her as an adult, that she couldn’t have it both ways. Your opinion?

— Not Sure of My Lane

Not Sure of My Lane: What will they do when she kills someone? Then will her son “have that discussion with her”?

This is not about love, or adult treatment, or rudeness, or anyone’s place. It’s about “lanes” only in the sense that the poor souls unwittingly on the road with your mother-in-law deserve to be safe in theirs.

People whose vision has deteriorated to the point they “can’t … see very well” belong nowhere near the controls for some thousands of pounds of rolling steel.

I do care about your mother-in-law’s feelings. I don’t see loss of independence as an abstraction. I will struggle mightily with surrendering mine, if I am lucky enough to have many years ahead of me. I resent that driving tracks so closely with independence to begin with, given that our culture went all in on cars and tolerated public transportation only as an afterthought at best.

But I care about people’s safety more than I care about all these things. More than I care about your husband’s mother’s feelings. It’s not even close.

And your husband is so selfishly obtuse, I could scream. If he wants a say in how this goes down, then he will have to start by getting his [priorities] out of his [stuck place].

But don’t wait for him. Resume the process the doctor started of seizing her keys; take the marital hit as a public service. The doctor, local police and department of motor vehicles all have a role, and each can steer you toward your next step. (For others just reaching this unfortunate crossroads: eldercare.acl.gov.)