What I'm saying here but I guess never got down to directly saying is this: While it's arguably not the BIBLICAL view (1 Cor. 7 goes both ways equally), the prevailing HUMAN view by marriage-book writers who purport their works to be "Christian" tends to be this: "The things a husband is expected to do for his wife are OBLIGATIONS to which a wife is ENTITLED, and it's wrong, even sinful, for him not to provide them. On the other hand, if and when she provides sex for him, it's to be considered only a cherished GIFT and PRIVILEGE which it's perfectly understandable and OK for her to withhold or make a low priority of at any time for any reason for however long a period of time she choses...and she is guiltless before God. But if the husband objects or pouts about this in any way, if he responds to this situation with anything short of unconditional love and unlimited patience, he's sinning big time.
Yes, my friend, that is the "Christian" attitude about sexual relations in marriage, as told by Christian sex book writers.
But it's not the Bible's viewpoint. I would argue that a person who isn't interested in sex - regardless of gender - has no business, and no Biblical right - to even dare consider getting married. To cheat another person out of their once in a lifetime opportunity to have the sex life God intends for the married person should be recognized as the MAJOR sin that it absolutely is, again, based on 1 Corinthians 7.