I would like to point out, respectfully, that there are other issues that hormonal contraceptives can treat. These include some types of ovarian cysts, pre-menstrual dysmorphic disorder, and some types of migraines. I would not go so far as to say that women on "the pill" for these reasons are abusing drugs, even if they are not sexually active. These women and their doctors should (and probably do) evaluate the risks of "the pill" against the benefits it may provide.
Personally, I too believe that sex should be reserved for marriage. But I think it goes a step too far to assume that contraceptives have no other use than to "liberate" sexual intimacy from marriage.