After a breakup there's the expectation that you'll eventually move on. But what if you can't? What if the impulse to think about an ex became all-consuming — months, even years later? What if it never goes away?

You'll find a few sufferers of this particular hardship on the "Limerence" subreddit, a message board where the brokenhearted and obsessed bare their souls. Some simply can't stop thinking about their unrequited crushes: "I probably think about her a hundred times a day," one user wrote, "right before going to sleep and right after waking up."

Others remain haunted: "It's been 14 years [that I've been obsessing over her]."

And for a few, the anguish takes a darker turn: "What's the point of living if 1) I can never have him and 2) I can never get over him?"

Psychologist Albert Wakin, a professor at Sacred Heart University, has spent a chunk of his career studying this type of lovelorn suffering. He thinks the problem is common enough that it's time for the psychology field to officially recognize that love can veer out of control and enter the realm of pathology. He hopes that obsessive love, or "limerence," will be included in a future edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM), though he doubts he'll live to see the day: Psychology and neuroscience research has only just begun to understand why romance has such a potent grip — and why, for all the people who can eventually get over a breakup, there are some who can't.

In 2007, a student approached Wakin after class with a psychology question of sorts: Why, she wondered aloud, could she not get over this guy? She didn't even like him — and yet she thought about him constantly; she felt like she needed him.

The student's struggles, Wakin recalls, instantly transported him to the 1970s, when he was a young professor at the University of Bridgeport. At the time, one of his colleagues in the psychology department, Dorothy Tennov, was investigating the early stages of romantic relationships — the period when you feel extreme and uncontrollable longing for the other person, when people describe themselves as "obsessed," "aching," "needy," "lovesick."

It was such a strange and powerful sensation, Tennov noted. It also seemed to be universal. And yet so little about it was understood.

She coined a term for this sort of love — limerence — and in 1979 published a book, Love and Limerence, which detailed the findings from her interviews of more than 500 people in love.

The response from the academic community was lukewarm.

"Tennov's term [limerence] results from a 10-year struggle to conjure a concept that adequately describes 'romantic love,'" a BYU professor named Spencer Condie wrote in Social Science Quarterly. "The significance of this book is largely semantic rather than scientific."

In other words: Great, so you spent a decade coming up with a word for something we already know about. Condie's attitude reflected what many at the time felt about the study of love: that it was trivial, maybe even impossible.


"My choice for the biggest waste of the taxpayer's money … has to be the National Science Foundation's squandering of $84,000 to try to find out why people fall in love," Wisconsin senator William Proxmire said in a 1975 press release. "No one — not even the National Science Foundation — can argue that falling in love is a science."

Even today, many involved in the study of love admit that it can be messy, especially with the slippery nature of the word itself.

"Love is this amalgamation of different feelings and emotions and behaviors, and science likes to reduce things to the most testable units you can find," Jeanette Purvis, a PhD student at the University of Hawaii who's conducting a study on Tinder, told me. "If I ask you and I ask my sister what love is, you each might say different things."

And yet Tennov, in her exploration of love's intoxicating effect, seemed to be on to something: "Letters poured in from readers who confirmed the book's conclusion," she wrote in the preface of the 1999 reissue of Love and Limerence.

Her hope, she added, was that "research directed at the physiological factors associated with limerence will settle the issue."

University of Hawaii social psychologist Elaine Hatfield is a pioneer of the scientific study of love and relationships. In the 1980s, she developed the passionate-love scale, a questionnaire designed to determine the intensity of someone's romantic feelings.

Passionate love and limerence, Hatfield told me, are "much the same." One of Hatfield's discoveries is that passionate love is a "high" — but as with all highs, it's fleeting. In most people, as a relationship develops, passionate love will fade, with another type of love — companionate love, an emotion associated with attachment and commitment — taking its place.

It turns out that "high" is an apt descriptor, neurologically speaking. In the late 1990s, neuroscientists Lucy Brown and Helen Fisher wanted to see what, exactly, was going on in people's brains during the passionate-love phase of a relationship. They recruited participants who had above-average scores on Hatfield's passionate-love scale, put them in an fMRI machine, and had them fantasize about their romantic interest.

In subject after subject, one part of the brain consistently lit up: the area that's rich in dopamine, the chemical that signals a reward and causes euphoria. It's the same area that's activated when you're on certain drugs, when you eat tasty food, or when you down a glass of water after a jog.

Here, finally, were some of "the physiological factors" that Tennov had hoped for, an explanation for why limerence had such a powerful effect on your thoughts and actions. Each reminder of the thing you desire activates the brain's reward loop: a craving, followed by the urge to fulfill it. It's why, when you've just started dating someone, you might reread a text ad nauseam. It's why marriage counselors will ask couples who don't "feel the spark anymore" to think about when they first fell in love.

It's also why, after breaking up with someone, being reminded of your ex makes you so miserable.

"Getting dumped is like withdrawing from any drug of abuse," Brown told me. "And what we know about trying to quit drugs is that you don't even want to see the drug."

From the perspective of the brain's reward pathway, the dilemma of all relationships, unlike drugs, is that they involve, well, people. "If a person is addicted to alcohol, you don't worry if alcohol will be available," Wakin told me. "When you're addicted to another person, you can't control whether they'll be there for you. It drives you nuts."

Facebook, for this reason, can be a minefield. When a photo of your ex pops up on your News Feed, the reward loop has been activated. You're simultaneously titillated and devastated; you long for what you once had, only to despair over the likelihood that it's forever lost. (Late last year, Facebook began piloting a "take a break" tool which allows users to temporarily prevent exes from appearing on their News Feeds or chat list.)

Back in 2007, after Wakin's student reminded him of Tennov's work, he got Tennov's number and left her a message. A few months later, his cell phone rang. It was Tennov's son. Dorothy had recently died, he said, but if Wakin wanted to come to Delaware, where she'd been living, he could review all of the research she'd done before and after the publication of Love and Limerence.

So Wakin and a grad student hopped in a car, drove down I-95 to Tennov's son's house near Rehoboth Beach, and began plumbing the dozen-plus file cabinets filled with Tennov's papers.

It soon became clear to Wakin that Dorothy's original idea of limerence needed to be tweaked.

"This 'thing' I aimed to study," she had written in Love and Limerence, "was a normal condition, not a pathological state." But Wakin noticed that, for a number people she had interviewed, the feelings associated with limerence — the constant thoughts, mood swings, and need for reciprocation — lasted longer than six months. And when they did, it was always detrimental to the relationship. This was not a normal condition.

"About four, five, six months in — what happens in a healthy relationship is that things settle down, they become calmer," Wakin explained. This makes sense; as Elaine Hatfield was able to show, passionate love will usually become companionate love. But in a "limerent relationship," the need for the other person only intensified. It was, as Wakin put it, "a love variance."

And it can be devastating. The object of the obsession will usually tire of all the attention and neediness, but attempts to create distance — up to and including a breakup — only make the obsession worse. In the worst cases, Wakin said, people he's surveyed and spoken with will have their partners (or exes) on their mind up to 95 percent of the time.

The exact sort of dynamic plays out on the limerence subreddit: "Gradually our conversations started to feel one-sided. I initiated them more often, they wouldn't last as long," one user reported. "I couldn't focus on almost anything other than him and when we would talk again."

Thus far, the research on these feelings has fallen into two categories. Wakin, Tennov, and others have documented the obsessive thoughts of those in the throes of limerence, while Brown and Fisher's neuroimaging studies highlighted the relationship between passionate love and the brain's reward pathway. But Wakin believes it's necessary to bridge the two. He hypothesizes that those who suffer most are struggling with a sort of dual disorder: a sort of obsessive-compulsive reaction to the object of their affection, and an addiction to them.

"One of those two things is not enough," he explains. "It's a combination." And it's this combination that he's trying to show in a series of brain-imaging studies.


Nor does obsessive love discriminate. "We are confident of this," Wakin says. "It can happen to anyone."

But therein lies one of the problems of getting it taken seriously. Many who become afflicted have no history of psychological illness, so they don't want to believe that something's wrong with them. And because love can be so fulfilling and positive, there's resistance to the idea that any aspect of the experience should be pathologized. For Wakin, it's difficult to convince people that he's not just trying to comfort people who are getting over a bad breakup.

Nevertheless, he hopes one day to see it included in the DSM ("the ultimate gold ring," he said) — naming it will make it real, and will promote the development of treatment strategies. But the DSM is a fickle document, a compromise of competing interests and intense lobbying. (As psychologist Gary Greenberg writes in The Book of Woe: The DSM and the Unmaking of Psychiatry, if you talk to anyone who worked on the most recent version of the DSM, they'll say that the guide's diagnoses and criteria are only "fictive placeholders" or "useful constructs.")

So for now, the emails continue to pour into Wakin's inbox, at least half a dozen a week.

"I respond to every single one," he says, "and I always offer an apology that the research isn't further along."

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