Maybe we love each other because we can’t help it, even if our rational minds know better. We pair up, at least for a little while, because we are literally addicted to one another. One often-cited study confirmed that the brain scans of the heartbroken resemble those of people going through cocaine withdrawal. Our species is designed for attachment, and these attachments have kept us reproducing and social, an evolutionary asset for bipedal, slow-moving mammals whose young take years to learn to walk and feed and look after themselves.
Naturally, severing these attachments is painful. Doing so is as ugly and complicated as breaking any other addiction. “We were not built to be happy,” Helen Fisher says, “but to reproduce.”
In their book The Chemistry Between Us: Love, Sex, and the Science of Attraction, Young and Brian Alexander describe the work of neurobiologist Oliver Bosch, who has experimented with prairie vole separation. Bosch put bonded voles through stress tests after separating them from their mates and found they consistently exhibited signs of depression. The most heartbreaking example is the “forced swim” test. Voles who were separated from their brothers (the control group) paddled manically when dropped into water, which is, apparently, typical rodent behavior: They are capable of floating, but when they are thrown into water, their survival instinct kicks in immediately. But the voles who’d been separated from their female mates didn’t do anything. As Young and Alexander put it, “The males who’d gone through vole divorce floated listlessly as if they didn’t care whether they drowned.”
Of course voles cannot divorce, because marriage is a distinctly human institution—one which has only recently been hitched to love. But knowing that the pain of heartbreak isn’t ours to bear alone is a small kind of solace.
Also take comfort in the advice that relationship success only comes after breakup failure.