Good advice, erion.
As a married man who gets laid now even more and better than he did when he was dating, I can categorically say, there's NOTHING about marriage by itself that necessarily means the End of Good Sex.
First, talk to her. She knows the edge is off too, I'm sure. Then start planning ways to spice things up. Pencil each other in for an evening of spontaneous time.
One thing that's recently hotted-things-up for lurkette and me is to have a shared fantasy. Ours right now is about another couple that we are totally lusting after. Stories during sex are very VERY fun.
And the other thing.... When I got married I suddenly found myself being different. You know, like BEING the way I thought a married guy should be. Sort of conservative, careful.... Being a lot like my father, actually. And it put the crimp on sex and a lot of other things for a while, until I sorted out how to be myself AND be married. You might look and see whether any of that is going on for you.