"Being able to step up to the plate even when you're not in the mood"... is what it means to act like a thinking spouse. Women who wait for their hormones or gift to put them in the mood are setting themselves up for failure in marriage.
Having the right attitude to get started and play along will get you in the mood, if your spouse is treating you with affection. And you are going to get much affection if you don't accept affection. By affection, I am referring to real feels of affection that are not sexual, the kind the women claim they want.
Because men are biologically wired to arouse more easily and serve women in heat, too many women only want to operate when they are in heat, and treat their husbands like an appliance. He has to tell her up front that he is not going to settle for cheap sex. What do you have to lose, if you are only getting mediocre sex 5 times a year? Anyone who has been to zero can tell you, there isn't any difference between zero, five, and ten.