The Biological Reason Sex Sometimes Becomes a Chore in Long-Term Relationships
Our hormones are a mirror that reflects our environment
Most of us by now have experienced the long-term relationship lull, the point of our dating lives where sex becomes difficult. Like Sisyphus, getting in the mood feels like we’re trying to push a giant rock up a hill, and we’ve been at it for an eternity. Your body feels heavy. Your arousal stops. Long gone are the endless nights of conversation, chats that lasted until one or both of you fell asleep on the phone with each other. And you have no control.
Conversations have taken the form of mumbles. “Hey. How are you? I’m good. Thanks for asking.” And your sex life is similarly drab.
If you’re lucky, you’ve not yet entered the “dead bedroom” phase of the relationship, and you’re still getting a little casual action. Maybe it’s a few times a week. Maybe it’s a few times a month. Or maybe it’s less frequent than monthly.
Either way, virtually everyone who’s been in a long-term relationship knows the feeling of the relationship going stale. There are thousands upon thousands of countless articles promising remedies for the feeling of not being in the mood anymore. There’s also a slew of products one can buy to “fix” this so-called “problem.”
“Just cut down on your stress,” they’ll tell you. “You know, stress accounts for a big part of why people lose their libido, right?” Or perhaps they’ll instruct you to try a different diet, or incorporate the right sex toys. What all of these suggestions have in common is that they act like it’s your fault.
The promise, of course, being that if you just made the right subtle changes to your lifestyle, both inside the bedroom and out, that you’d finally reinvigorate that spark you once had. If you just made the right choices, instead of the wrong ones, you’d once again feel the rush of adrenaline, the dopamine surges that resembled a dose of cocaine straight to the brain, and the high testosterone levels that kept you ferociously attached to your partner like Gorilla Glue.
But what if it wasn’t so simple? What if this natural process wasn’t anyone’s fault?
What if all of these tips and tricks were trying to “fix” a “problem” that wasn’t meant to be fixed? What if your newfound state of low-key, long-term relationship status wasn’t a problem at all, but how we humans were designed?
To understand this, it’s important to look at our biology and see how and why we evolved to fall in love, have sex, and form stable relationships. So, before you go trying everything under the sun to reignite the old flames of your past, it’s important to understand what we’re up against.
In the Beginning…
The beginning of a new relationship always starts with a massive eruption, where suddenly we’re thrust into a new state of existence. Every waking moment is spent thinking about our new partner. We crave their bodies. We can’t get enough of them.
This stage of love is called Limerence in biology, and it happens in both the human and animal kingdoms.
Creatures ranging from elephants to dogs experience the passionate, sex-crazed phase called Limerence, where they are granted almost godlike powers. They’re energized, youthful, hopeful, and most of all aroused. Their testosterone raises to new heights. They feel daring and invincible. And we humans experience these same feelings — with the corresponding rise in hormone levels.
Possibly the most fascinating thing about Limerence is that only certain compositions of chemicals (other people) are thought to cause it in us; that is, it takes place on an extremely small biological scale, operating from the ground up. Only certain people (compositions of chemicals) can cause this chain reaction of chemicals within us. As without, so within.
If you’ve fallen in lusty love with a partner, chances are pretty good that you didn’t intend for that to happen. You likely just met someone special and your body did the rest of the work from there.
But just as quickly as the rush of desire came on, so too it faded away. You just put in the time and fought against the tide of inevitability, but eventually, yet again, your body did the work for you.
The rush of hormones subsided. And now you feel complacent where you once felt supercharged.
Understanding Relationship Orientations
Like other sexed animals, humans evolved relationship orientations that serve different purposes. After much robust debate over the question, “Did we evolve to find the perfect partner, or to spread our love out among many partners in a ‘mixed’ mating strategy,” contemporary science is going with the latter. A “mixed” mating strategy doesn’t preclude finding the perfect partner. But finding the perfect partner precludes a mixed mating strategy.
Sometimes, we hold out for the best partner we believe we can get, the Romeo to our Juliette, the match made in Heaven that Shakespeare wrote about centuries ago.
Other times, we date around, we test the waters of different people knowing each of them will have benefits and drawbacks, we sometimes cheat, we sometimes end up in open relationships, we sometimes play the field.
Both strategies are native to us humans, you see. We can do both.
In Psychology Today, writer EE Smith says that monogamy isn’t natural among human beings, but she notes, referencing the work of evolutionary biologist and Professor David Barash, that we’re capable of it. She goes on to chime on a voice from the other side, saying that we also carry the genes for poly relationship styles, and even going as far as to suggest that, in the long run, the genes that tell us to be polyamorous may inevitably win.
This is because much of what we consider “falling in love” takes place on a chemical level. And our bodies evolved to do this for good reasons. Those reasons have to do with the conflicting goals of seeking out new potential partners and child-rearing.
When we seek new partners, we’re in what’s called a “competitive” relationship orientation. Our bodies understand this without us ever so much as thinking about it. Our testosterone levels are higher. Our bodies tell us to go find someone and hurry up and get partnered. We swipe right on him, swipe left on her, and we go out to singles bars while we compete in the search for someone who makes us happy.
When we find a partner we really, really like, our disposition changes — and so does our chemical make-up. Our hormones shift. The testosterone that gave us the rush we so adored subsides. And this is called a “bond-maintenance” relationship orientation.
The point of this orientation, in evolutionary terms, was to keep us from having a ton of kids and getting out of dodge as fast as possible.
It’s as if our bodies know when we’ve got to devote ourselves to our partners and settle down if the human race was going to survive.
The chemicals that once told us to buy a classic car and jeans that hug our asses to draw attention toward us have now been replaced by chemicals that tell us to buy a house in the suburbs with top-notch schools, to buy cargo shorts and sandals, and to focus less on attracted attention and more on maintaining the commitments we’ve established.
But what if this process wasn’t so black and white, either?
Multiple Partners and Testosterone
The most interesting thing about all this is the fact that people who have multiple partners instead of just one have higher levels of testosterone. Testosterone is a major sex hormone that plays a role in, among other things, libido, sex drive, and sperm production in men.
And people who are in poly relationship orientations don’t experience the long-term relationship “dip” in testosterone that everyone else does. And now, science has put this to the test, publishing the results in a piece titled Multiple partners are associated with higher testosterone in North American men and women.
Over the course of a year, scientists measured the testosterone of various people engaged in different types of relationships. Scientists took blood testosterone samples throughout the experiment, and the results were striking.
Single people had more testosterone than partnered people. And even more interesting than that, people who were in polyamorous or poly lifestyle relationships (polyamorous but currently without a partner), had more testosterone than either the single group or the partnered group.
Now you might be wondering, is this because people with higher T are more likely to be multi-partnered, or is it that becoming partnered alone is what lowers T?
Well, while there’s still much to be learned, after confounding the variables, researchers were able to say it’s a bit of both:
The data are beginning to consistently point to an association between relationship orientation and T in men, but the association between T and partnering in women appears to be either more complex or less immediately apparent. In women, data support both a state interpretation (i.e. that relationship status is associated with T) and a trait interpretation (i.e. that T predicts partnering). Still, lower T is at least consistently found in women who are in relationships with one person.
In the End…
While it may be depressing to think about, humans might not be particularly well-designed for lifelong monogamy, no matter how much we want to believe we are. And that’s okay! It’s okay to settle down in the suburbs and buy a minivan, it’s okay to rock cargo shorts and socks — with sandals — when you once wore a ripped Motley Crue t-shirt and dusty jeans.
But it’s also okay to be multi-partnered if you want. We now live in modern, technologically advanced societies, and we’re capable of having kids on weeknights and finding a babysitter for wild nights filled with steamy sex and new partners on weekends should we so choose.
The choice is ours. And that’s where the magic lies.
If this science tells us anything, it’s that people who’ve chosen to add additional partners into their relationships to “spice things up” may be on the right track. Perhaps they were naturally able to intuit the fact that our bodies change over time, our desires wanes when we’ve found our life partner, and that introducing new partners into the mix just might be the way to keep things most alive.
But, of course, non-monogamy isn’t for everyone. Some people may decide to go the old-fashioned route and that’s okay, too. Each person has to decide what’s right for them and if humans are anything, we’re flexible and adaptable.
Hopefully, this helps you find a little understanding about your own sex drives, your feelings, and the experiences you’ve had in your life.
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