It's remarkable that, even though his youthful lusts seared themselves into his memory and provoked confession of sin, Augustine didn't counsel the extinguishing of desire. He knew that desire is inevitable; even more, it is instructive. Desire carries with it an intimation of immortality. Every one desires God, Augustine insisted, whether she knows it or not; and carefully studied, desire can indicate the One who has made us for himself, such that our hearts are restless until they find their rest in him. One problem with never asking what we are to do with what we want is that we fail to consider the One we really want, in all our varied and, often enough, vicious and vacuous cravings.
And so, Augustine didn't counsel the frustration of desire. He called for its acknowledgment, education—and education so profound it was a conversion—and, finally, its fulfillment in the only One who can fulfill it.
Christians who don't have sex aren't frigid; like everyone else, they burn with desire. It's just that they, unlike many, know what they really want.