For some men, love and sex don't mix. They save love and marriage for "good" women, and only enjoy sex with "bad" women.
In cases of the Madonna/Whore Complex (or Syndrome), a husband's relationship with his wife may be based upon the unmet intimacy needs he had as an infant. He may unconsciously seek out a woman who reminds him of his mother so that those needs can finally be met.
When these men marry, they marry a "good" woman. For them, virginity or the lack thereof, divides "good" from "bad." They will love her, protect her, and treasure her.
They don't feel comfortable having sex with her once they marry. It would be "dirty," like having sex with their own mother, the purest "good" woman in their life.
When or if their wife becomes a mother, the lines blur even more for him between his wife and his mother.
The Madonna/Whore husband will be sexually active but not with his wife. He will have sex outside of marriage, not for love but because he has an active sex drive.
A virginal and sexually inexperienced woman who falls in love with a Madonna/Whore man may not have even the slightest clue that there is something very wrong within their relationship.
She may be thrilled to have found a man who places her on such a lofty pedestal, who worships her, who is so concerned for her well-being.
During courtship, he may have been quite passionate. At that time he may have been "testing" her to see if she was sexually experienced or "easy."
A sexually inexperienced young woman may think it is her very inexperience that is responsible for her husband's lack of interest. Over time, she will question her attractiveness, wondering if there is a way to make herself more sexually appealing to him.
Her attempts at sexual seduction may backfire, with him accusing her of acting like a "whore" or telling her she looks stupid or whorish.
His rejection is a terrible blow to her self-esteem. It is particularly cruel when she observes the interest her husband shows in other women.
Even the most inexperienced women consider sex and love to be a package. For women who were taught "good girls don't," marriage was supposed to be when "good girls did."
Love, for women married to such men, is essentially sexless. They may have had enough sexual encounters to start a family, but with children came even more sexual distance. When she becomes a mother, he has even more reason not to "defile" her with sex.