When love goes sour, the fallout can be severe — just check out the song list of any Taylor Swift album.
But what does science have to say about the emotional aftermath of breakups? It turns out that just like relationships themselves, separations can be complicated. How people respond depends on factors like how they felt about the relationship in the first place, how entwined their self-image was with their partner's and even how their partner reacts on social media.
Here are the cold, hard facts about splitsville.
Breakups are predictable
Ever been through one of those breakups where you were the last person to see it coming? It may sting when your friends nod knowingly when you tell them you're single, but here's even worse news: Science probably could have given you a warning, too.
A 2010 study published in the journal Psychological Science asked 222 volunteers, all of whom were in relationships, to say their partners' names and then give two words they felt were related to them.
Next, the researchers did a test of implicit association, which uncovers feelings people might not even admit to themselves. They paired the partner-related words with either positive words (e.g., "gift") or with negative words ("death") and asked the participants to press a button either when the word was linked to a positive or to a negative.
The idea is that if a person feels positively about the word they gave about their partner, they will be faster to press the positive button when the word is linked to positive words. If they feel negatively, they will be quicker to press the button when the word is linked to negative words.
It turned out that the people who were faster to link their partner-related vocabulary to negative words were also more likely to split up over the next year than people who were faster to link their partner descriptions with positive words, the researchers found. This was true even when controlling for relationship satisfaction and conflict. [8 Myths That Could Kill Your Relationship]
"This suggests that the earliest seeds of relationship decay might be found within attitudes that subjects might be unaware of or are unable or unwilling to report," the researchers wrote.
Breakups are about identity
The more committed a couple, the more that each person's sense of self begins to overlap their partner's, according to a 2010 paper in the journal Personality and Social Psychology Bulletin. A series of studies — relying on surveys and daily diaries — found that a breakup can disrupt a person's sense of self, leaving them adrift.
College students who'd been through a breakup were more likely to use words like "confuse" and "bewilder" in daily diary entries than those who hadn't, the researchers found. They were also more emotionally distressed than people who hadn't lost their relationships, according to a six-month survey in which students filled out questionnaires each week. Notably, the less clear the students felt about their own self-concept, the more distressed they were after a breakup.
"Couples may not only come to complete each others' sentences; they may actually come to complete each others' selves," the researchers wrote. "When these relationships end, individuals experience not only pain over the loss of the partner, but also changes in their selves."
Dwelling might be healthy
The post-breakup ritual is sacrosanct: Ice cream, pajamas, sappy movies.
A little bit of wallowing may be a good thing. When researchers asked recently single people to participate in intensive sessions exploring their feelings about the breakups, they found that these individuals actually recovered better than people who participated in just a few short sessions. The results, reported in 2015 in the journal Social Psychology and Personality Science, were somewhat counterintuitive.
"At first glance, it might seem like repeatedly reminding participants that they had just broken up — and asking them to describe the breakup over and over — might delay recovery," study researcher Grace Larson of Northwestern University said in a statement. But instead, Larson said, lingering for a while in a self-reflection phase appears to help people put the past behind them.
But don't dwell too much
Thinking about a breakup might be beneficial, but try not to torture yourself. Research finds that obsessively checking Facebook to see what your ex is up to is probably not a good idea.
In a study of about 500 mainly college-age women, researchers found that those who spent more time checking their ex's Facebook page were more likely to report experiencing distress, negativity and longing for their partner, and less likely to experience personal growth after a split. It's hard to tell from the research whether the Facebook stalking was causing the distress or vice versa, but the social media site didn't show any sign of helping, according to the study published in September 2012 in the journal Cyberpsychology, Behavior and Social Networking.
However, defriending an ex might backfire: People who weren't Facebook friends with their ex were just as bad off as the obsessive Facebook stalkers, the study also found. Cutting off all contact with an ex might shroud his or her life in appealing mystery, the researchers suggested, whereas occasional exposure to boring status updates might bring the ex's memory off a pedestal.
It's hard to let go
If you just can't shake a breakup, don't beat yourself up. Romantic rejection is not unlike kicking an addiction, according to 2010 research in Journal of Neurophysiology.
The researchers looked at people who had recently experienced a breakup and who said they were still in love with their exes. The participants underwent brain scans while looking at photographs of their former flames, as well as photographs of other friends and acquaintances.
When looking at their lost love, the volunteers showed brain activity in a region called the ventral tegmental area, which sits in the midbrain. This area is known to be activated when people are in love, and in situations involving motivation and reward. Other reward- and addiction-centered areas, including the nucleus accumbens in the forebrain, also became more active. [5 Ways Love Affects the Brain]
The good news is that the strength of the activity faded with time, the researchers reported. No matter how stubbornly the brain holds on, it eventually lets go.
It differs by gender
Anyone can experience heartbreak. Still, how you experience it might depend, in part, on your gender.
Women report higher levels of emotional pain, anguish and even physical pain after a breakup than men, according to a 2015 paper in Evolutionary Behavioral Sciences. For example, on a 10-point scale of pain, women rated their post-breakup anguish at 6.84, on average, compared with 6.58 in men. More than 5,000 people in 96 countries participated in the study, which included gay as well as straight respondents.
It might not be as bad as you think
However you slice it, breakups are rarely easy. But there's a silver lining: We often overestimate how bad they'll be.
People bounce back from breakups about twice as fast as they'd expect, and they aren't nearly as devastated by the relationship loss as they predicted they'd be, according to a 2008 study in the Journal of Experimental Social Psychology.
The researchers tracked 70 undergrads in relationships over time, asking them weekly about their relationship status. Some of these questions had to do with how the person expected to feel if their relationship ended. People expected it would take about 20 weeks to emotionally recover, on average.
But among the 26 people who did experience breakups during the study period, it actually took about 10 weeks to get back into the groove, the researchers found. And people's actual distress was much lower than they'd predicted before the relationship went south. [13 Scientifically Proven Signs You’re in Love]
"Life goes on in the wake of a breakup," study researcher Paul Eastwick of Northwestern University told Live Science at the time. "And when you're making your predictions, you aren't thinking about all the things that could be positive that might happen in the next week or two."
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Stephanie Pappas is a contributing writer for Live Science, covering topics ranging from geoscience to archaeology to the human brain and behavior. She was previously a senior writer for Live Science but is now a freelancer based in Denver, Colorado, and regularly contributes to Scientific American and The Monitor, the monthly magazine of the American Psychological Association. Stephanie received a bachelor's degree in psychology from the University of South Carolina and a graduate certificate in science communication from the University of California, Santa Cruz.