I think that the most useful piece of information found in any book on relationships, whether romantic or otherwise, is the reminder that men and women think differently.
It's not necessarily good news to note that your actions are "typically female" or that a guy's mysterious behavior is "typically male" (or vice versa). But when viewed in light of the fact that we are created by a loving God, and that He orchestrated all of this to His glory, it all starts to make sense.
"Lady in Waiting"* accomplishes this goal. It presents the ways that a woman can be feminine in Christ, developing the qualities that her Creator designed for her.