(Washington Post illustration; iStock)

The pain started on the way down the mountain, a dull ache in my chest that became more acute as the miles accumulated. The morning had been a blur of hungover goodbyes as a three-day camping wedding of close friends came to an end in Northern California. It wasn’t until I was in the quiet safety of a friend’s car that I allowed myself to feel the effects of my conversation with my date the night before.

He had told me he wasn’t interested in trying a relationship. Remembering it made the pain intensify. By the time we reached the interstate, I was in tears.

Our relationship had been mostly one of potential since we’d been introduced in a San Francisco bar by one of the newlyweds two years before. We lived 3,000 miles apart, and although we marveled over our powerful connection every time we were together, our love affair had been limited to brief, intense hookups whenever we happened to be in the same place.

But being with him wasn’t like being with anyone else, and I’d been single long enough to know how rare this feeling was. I screwed up the courage to ask whether he was interested in finding out where this could go for real.

His response, though not the one I’d been hoping for, was kind and fair and didn’t come entirely as a surprise. The surprise was how much it hurt — not just emotionally, but physically. My heart ached all that long car ride back, and it hurt later that night at another friend’s house at Ocean Beach, where I drank too much wine and cried again. The pain lingered the next day and for weeks afterward, as if a vice were squeezing my chest. Sometimes it would let up, but clench down again at the slightest trigger.

We tend to think of heartbreak as purely emotional pain but forget that we give it a physical dimension with our term for it. Some feel it in their chest, as I did; others feel it as a stomachache or a more diffuse pain all over the body. Humans seem to have been feeling it since at least the 1300s, when the word “heartbreak” first made an appearance, according to the Oxford English Dictionary. Several languages have a similar word translating to something like “heart pain.” 

Social scientists believe that the phenomenon has been around for much longer, possibly millennia. Like grief, our physiological response to rejection is triggered by some of our deepest survival instincts. Humans are herd animals who depend on one another to survive. To keep us from drifting away from the fire every time we had a disagreement, our brains developed a physical alarm system that warned us when we got too far from the people who helped keep us alive in the wilderness.

“A social rejection hijacks the part of our brain that signals pain to say, ‘Hey, this is a really serious situation,’ because just like physical pain, the consequences could be there,” says Ethan Kross of the University of Michigan’s Emotion & Self Control Lab. In 2011, his lab conducted a study in which researchers showed participants pictures of an ex-partner who had broken up with them. Seeing the photo activated the same brain regions previously thought to be specific to the experience of physical pain. Other emotions, such as anger, don’t do that.

But that doesn’t mean emotional and physical pain are the same thing, Kross cautions. Even though physical pain and rejection activate the same parts of the brain, they have different neural signatures, which is why humans can tell the difference between the agony of a broken leg and the sting of a social slight.

Right now, Kross’s lab and others, such as the Social and Affective Neuroscience Laboratory at the University of California at Los Angeles, are trying to figure why and how the processes overlap, but they agree that the underpinnings are probably evolutionary.

Today we don’t need tribe members helping us fight off saber-toothed tigers, but we still need other people to get through our lives. Studies at UCLA and the University of Arizona have shown that people are better off, physically and mentally, when they have stronger social connections. Extreme loneliness can trigger stress cardiomyopathy, colloquially known as “broken heart syndrome,” where emotional stressors will cause an otherwise healthy person to suffer something like a heart attack.

For most of us experiencing rejection, the pain is a signal to step back and be mindful, like sore muscles when we’ve been pushing our bodies too far in a workout. Heartbreak is “a functional response telling you, ‘Look, something really important just happened,’ ” said Geoff MacDonald, who studies social connection and emotional experience at the University of Toronto. Although they’re painful, he thinks the bad feelings of rejection provide a hugely important learning opportunity if you’re willing to listen. “You need to stop. You need to reestablish connections with people. You need to understand what happened and why so you can make sure it never happens again,” he said.

Of course, it will happen again to most of us, again and again and again — just hopefully not with the same person or as part of a bigger pattern. As I processed my own heartbreak, I realized that I’d been following MacDonald’s advice without knowing it. Instead of keeping how much I was hurting to myself, as I’ve done before, I threw myself into a summer of friends and family and was upfront about what I was going through. Their kindness and acceptance in the face of my vulnerability didn’t cause the pain to stop immediately but did remind me how much love was already in my life; their support gave me a protective shell as I healed.

As the months have gone by, I’ve also reflected on my not-quite-relationship with this man. I’d gotten carried away with the potential and ignored the signals that he wasn’t up for investing in a long-distance romance — no matter how much chemistry we had, no matter how much we made each other laugh.

But at least I’d asked for what I wanted. For years I’d been settling for one unavailable man after another and scraps of relationships on their terms without ever asserting my own out of fear of losing them. Now the worst had happened and it was painful, but it was also freeing. I might have lost this round, but I’m glad to be back in the game.

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