And, I'm not meaning to suggest that there is something wrong with YOU, but have you had your hormones checked? I know that my exe's sex drive was DIRECTLY tied to hormonal balance. Her already low sex drive took a nose dive when she had an early hysterectomy. Zero interest in sex, and sex itself became painful and uncomfortable due to lack of lubrication. When she talked to her doctor, they gave her some hormone cremes and gels, and her sex drive went through the roof. (Unfortunately, when she realized how much her desire was tied to such simple chemistry, she stopped using the hormones because she felt her desire wasn't sincere).
And it's been my experience that lack of desire can eventually weak havoc on a marriage. This is something I never really ascribed to, and always thought that the passion would come along if the partners were well matched on other levels. We were badly matched sexually. I was always ready, willing to try anything, but she simply didn't feel the same way for most of our marriage.
Sadly, the lack of desire on her part was pretty much the last straw, though our relationship by that time had degraded for other reasons. I divorced her, and in the end, the lack of passion was a factor. I could tell she simply wasn't interested, and I got tired of what amounted to duty sex.
After divorce, I met and married my wife. We were in our fifties, and our passion for each other is mutual. We are well matched on all levels. But we BOTH have a past that speaks to the problems a lack of passion can bring.
Sexual attraction may be of secondary importance philosophically, but it lack of it can eventually be a problem. It certainly was a factor in my wife's previous marriages. She was married for many years to the father of her children, but they had a very unsatisfying sex life. She married too young, she was sexually inhibited, naive; and her husband was not a passionate person. They married because they thought they were right for each other. He was, in many ways, an ideal husband and father. However, they slept in separate beds, and sex, while he enjoyed it in his own way, was essentially passionless. She he experienced her first orgasm spontaneously after years of marriage. She could NOT change her husband to make him more attractive to her, or to turn her on, or give her pleasure in any way. Lack of attraction ended her marriage, and she ended up in a disastrous second marriage to a serial cheater who she was smitten with -- and who gave her the passion she had been missing.