Hi, Carolyn: I'm married for 40 years and I've had health issues, most happening in the past five years. My husband is completely detached and uninterested. He never follows up with test results, and he forgets appointments he promised to come with me to, some pretty serious — I had lung cancer three years ago. He's never asked me, "So when's your next CAT scan?" or, if he knows I went for a scan, never follows up.

He had one heart issue six years ago and I was by his side the entire time.

Now that we're in our 60s and things are starting to happen health-wise, I need someone by my side who will take care of me, and I don't see that ever happening. I'm not sure what to do. Even when I decide to just deal with everything alone, it's just so hurtful and I end up fighting with him about it.

Whenever I've asked him why he thinks he's like that, he just says, "I don't know." When I say, "Well, the next time you get sick, I will not be there for you," he says, "I don't blame you."

How is that a marriage, especially approaching the last years of our lives?

— S.

S.: The most forgiving explanation I can think of is that he’s terrified of illness in general and of losing you in particular, and just freezes.

The most useful explanation I can think of is that he’s bad at this, and would be bad at it with anybody, so it’s not as personal as it feels.

His “I don’t blame you” says he knows he’s wrong. It seems he’s not deliberately hurting you so much as completely shutting down. (So maybe rethink your tit-for-tat.)

If any of this helps you fathom his detachment, then feel free to make it yours. Or bring the whole question to (tele-)therapy, with him or solo — because this appears beyond fixing, which leaves you with accepting.

And accepting means finding other rewards and other value in your marriage besides medical support.

Does that seem narrowly defined? I did it on purpose. You can set the scope of the problem as wide as you want:

Widest: He doesn’t care.

Narrower: He is not a caregiver.

Narrowest: He hears “doctor” and bolts like a roach in daylight.

Which one fits, and which can you live with?

I also urge you to recast “dealing with everything alone” as “dealing without him” — which is far less dire.

It’s so unfortunate, and I understand your despair. None of my suggestions for working around him is meant to deny how he’s failed you. But once you’ve faced your disappointment, dwelling on it — and continuing to expect him to play a role he has repeatedly proved he can’t play — only prolongs your suffering and sets you both up to fail.

Accepting you can’t count on him frees you to plan accordingly, to count on others. Take your cue from the millions of over-65s who live alone and/or don’t have caregiver-relatives (for whatever reason), and develop a personal support system. Talk to friends about backstopping each other; meet with a geriatric care manager; put in a call to a helpful person from your cancer-care team. Check your insurance. Call your local council on aging. Call it Plan Be.

Write to Carolyn Hax at tellme@washpost.com. Get her column delivered to your inbox each morning at wapo.st/haxpost.