Hard truth coming up here but at least it's truth.  You and your wife are just fine, nothing wrong with either of you.  The difficulty lies in the unavoidable and as far as I've ever heard universal hassle of getting overly used to each other/bored of each other in a long term monogamous relationship.  no matter how real the love, boredom and the related sexual problems creep in. 

It also seems standard (though not always) for men to try to break through the malaise that sets in by saying, "Hey, still need sex over here, aren't I doing right by you?" while women drift to the ongoingly refreshed relationships that are friends and family.  Those relationships get refreshed by ABSENCES.  Husband and wife are face-to-face 24/7.  That unrelenting proximity has never in the history of the human race been a source of sexual energy for people.  You've heard the phrases: familiarity breeds contempt, a change is as good as a break, etc.  In all aspects of life, human beings seek out change and difference and novelty because we are designed to seek and explore.  It's our nature.  Only recently in history have people started to marry for romantic love.  In all other eras, it was familial and economic demands that motivated people to wed.  Women were oppressed and repressed sexually; men slept with other women when they needed to, usually got away with it, women strayed too and hoped not to get caught.  Oh there was love throughout history but people found ways to be sexual outside love when needed.

In the western world, all that changed with the rise of the modern religious marriage and the establishment of the widespread belief in romantic fulfillment through one other person.  It doesn't work for sex.  You're discovering this.  You love her to death like I do my wife, but when the same compliment from other people that you givey your wife means more to her, light her up more, when you get on her nerves more than in her arms, you starts to realize the effect of this crazy game we try.  You've been married 5 years, me 17.  The only times our love life got shocked back to life (and the sex was more frequent and real, with our hearts in it)  was when we fought and came close to breaking up and spent time socializing a lot separately with others.  This brought us back into novel and community and away from each other having to be responsible for ALL of our needs, which, when you think about it, is a crappy thing to do to someone.

I say all this because her I am on these forums again looking for an answer to this problem myself pretty much.  The post about the house not being a sexual space is mine.  Things are a little better now because we're older and with the kids I don't want our sex-regenerating near breakups to take away the energy we need for our lives.

It's your generation that might be able to fix this problem.  too late for me. Men and women need to recognize that it's okay to get fired up by other people; it fires you up for each other.  Open marriages with strict rules will be the way to go.
Good luck.