Most evenings you offer me your feet to stroke. I always oblige. Yet even after 15 years of marriage, I still don't understand the exchange rate. Just how many foot strokes must I give before you might reciprocate the physical contact?

When you occasionally do, it's only on a Saturday, long after our last child is asleep. I no longer dare ask out loud, since your "No" is so final, while your "Maybe" may give me false hope. I just wait as you unwind watching television. How can you prefer endless reruns of Morse to me? Then you utter those three words as you get into bed: "I am knackered." My heart sinks.

I know we owe our comfortable lifestyle to long working days made more frenetic by three energetic kids, but I'm tired of you being tired all the time. Do you have to go to the gym quite so often? Must you devote so much energy to the PTA?

I could understand if our bodies were not in tune with each other on those rare occasions when you give them the chance. During the increasingly long in-betweens, I ache for you. Not for sex, but for sex with you. A sexless Saturday night doesn't bother you because there will be plenty more. But to me, it's another week without you, and weeks turn quickly into months.

Have I simply "served my purpose"? Once I plucked up the courage to ask if sex was important to you. You said it was. Perhaps it is just less important to you than it is to me.

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