Shrug, Actually

I'm in my first serious relationship. It started off super hot and sexual. Now, a year in, it's lovey-dovey and cuddly. Not that my boyfriend and I don't have sex. We do, and it's still good. But we no longer sext or send cute selfies, and the butterflies feeling is gone. Is it all downhill from here?

--Worried

Once you've been together for a while, you may still have vivid fantasies running through your head during sex, like the one where you get to the dry cleaner's before closing time. The Declaration of Independence proclaimed that we have a right to "the pursuit of Happiness," but it doesn't get into actually having it, which, as you've discovered, can be a bit of a bore. This makes biological sense, considering that there are stages in attraction and bonding and a cocktail of biochemicals behind each. Dopamine, a neurochemical that researchers associate with wanting, "novelty-seeking," and focused attention, is a star player when you're in chase mode (aka "infatuation," "attraction," or, more descriptively, "Who knew you could get a callus down there?"). However, evolution is no fool, and it realized that we couldn't spend all of our time chasing each other around whatever passed for the kitchen table back when "the man cave" was an actual cave. So bonding hormones -- oxytocin and vasopressin -- eventually take charge. And that's why, a year into a relationship, you may be doing "unnatural acts" in the bedroom, but they probably involve things like dusting the miniblinds. Going from hot sexts to ho-humming along is a result of "hedonic adaptation." "Hedonic" comes from a Greek word for pleasure, and hedonic adaptation describes how we quickly acclimate to changes in our circumstances -- positive or negative -- to the point where they no longer give us the boost (or kick in the teeth) that they first did. Research by social psychologist Philip Brickman and his colleagues suggests that we each have a happiness "set point," and we keep getting pulled back to it. A fascinating example of this is their finding that people who won big in the lottery were (of course) stoked at first, but ultimately, they ended up being no happier than victims of crippling accidents. Happiness researcher Sonja Lyubomirsky finds that people in relationships can resist hedonic adaptation, but it takes "ongoing effort" to bring in variety. She's talking about varied experiences and, especially, varied surprising experiences. Surprise, Lyubomirsky explains in "The Myths of Happiness," delivers "strong emotional reactions." Remember strong emotional reactions? They're a little hard to come by once you can close your eyes and draw a solar system of your beloved's every birthmark, freckle, and mole. The good news is that, even now, you can bring surprise into your relationship; you just need to stage it. Try to inject it into every day, and maybe take turns planning a weekly secret date night -- secret from the person who isn't the planner -- so at least one of you is surprised. You might also take turns planning separate sextracurricular activities, on the same model. Without this extra effort, sex may still be fun, but the only way it's likely to be surprising is if one of you tries to sneak out the window afterward.