Retard, the point is that it's likely both and some kind of cycle. Both men and women cool off in different ways after the initial passion/infatuation of the early relationship. And so it's a vicious cycle. Men become less romantic, which in turn leads to less interest from women, for whom romance is a huge component of sex. And as the women in turn are less interested in sex, it reduces the romantic feelings of the husband even more ... thus the vicious cycle.