Germanshepherdsmum
Your husband’s sense of smell might not be good or he may have become, as the ad says, ‘nose blind’. Even if your hair doesn’t get greasy it absorbs smells in the air around you, and remember your scalp will sweat. My hair’s below my shoulders and I wouldn’t dream of not washing it a couple of times a week at least.
A former colleague of mine (similar age to me) had very thick, coarse-ish hair, which she washed only once a week. I was often physically very close to her and her hair never did smell - and I’ve always been very conscious of that stale, unwashed-hair smell. In former times it wasn’t uncommon to smell it when sitting behind someone on the bus.
I would also smell it on my mother after she became very difficult about showering/hair washing because of dementia.
I used to envy that colleague because my hair (very fine) still needs washing every 3 days max and pref. every other day, to look nice.