If you've been surprised by how much a break-up hurts, you're in good company. People describe it as a weight on the chest, or as being unable to eat or think about anything else. Some find that it hurts more than losses that look bigger from the outside. Psychologists have spent a long time studying why, and what they've found may make the next few weeks a little easier to understand.
You've lost more than a partner
Attachment researchers think of a long relationship as an attachment bond. Your partner became the person you turned to when something went wrong, and the person whose presence settled you. When the relationship ends, you lose that, on top of losing the person.
This explains something many people notice. The pain doesn't always match how good the relationship was. A relationship you knew wasn't right can still hurt badly to lose, because the bond was real even when the fit wasn't.
Why it can feel like a physical pain
In one study, 40 people who had been through an unwanted break-up in the previous six months looked at a photo of their ex while thinking about the break-up. The brain areas that became active overlapped with areas involved in feeling physical pain (Kross and colleagues, 2011).
It's worth knowing that other researchers questioned this. They argued that a photo of someone you still care about is so emotionally loud that it could light up those areas for other reasons (Iannetti and Mouraux, 2011). So the honest summary is that the brain treats the loss as something big and urgent. Whether it's literally the same as physical pain is still argued about.
Why you keep going back to them in your head
A smaller study scanned 15 people who had recently been rejected and were still in love. Looking at their ex activated areas involved in reward and craving (Fisher and colleagues, 2010). The researchers compared it to withdrawal. That's an interpretation from a small study, but it fits what many people feel: the pull to check their messages, to look at old photos, or to work out what went wrong for the hundredth time.
Why it's often worst at night
During the day there's work, other people and things to do. At night it's quiet, and the thoughts have room. In a study of 192 university students after a break-up, those who were most distressed also had more intrusive thoughts about it, found those thoughts harder to control, and slept worse (Field and colleagues, 2009). Feeling betrayed, and the break-up being recent, were among the strongest predictors of distress.
If you're lying awake going over it, that doesn't mean you're handling it badly. It's one of the most common parts of a break-up.
Why it hits some people harder
How we attach to the people we love shapes how we come apart from them. In a survey of more than 5,000 people, Davis, Shaver and Vernon (2003) found that people higher in attachment anxiety (a deep worry about being left, or about not being loved enough) reacted to break-ups with more preoccupation with their ex, more physical and emotional distress, and more attempts to get back together. People who felt more secure were more likely to lean on friends and family.
If that describes you, it isn't a flaw in your character. Attachment patterns usually go back a long way, often to how safe and cared for we felt early in life. A break-up can wake up that older feeling that nobody is really there for you, and that's part of why it can feel so much bigger than this one relationship.
It does ease, and you can help it along
In a study that followed 58 young adults for four weeks after a break-up, love for the ex declined steadily over time. Sadness and anger eased too, in a less even way, with ups and downs along the way. Staying in contact with the former partner slowed the decline in both love and sadness (Sbarra and Emery, 2005).
A few other findings point to what helps.
Getting your sense of yourself back. After a break-up, many people feel less sure who they are, and that confusion is linked to more distress (Slotter, Gardner and Finkel, 2010). In a later study, people who regularly reflected on their break-up over nine weeks recovered a clearer sense of themselves, and that went with less loneliness and fewer intrusive feelings about it (Larson and Sbarra, 2015).
Less checking. In a survey of 464 people, those who kept looking at an ex's Facebook page had more distress and longing, and less personal growth (Marshall, 2012). The study can't show cause and effect, but muting or unfollowing is an easy thing to try.
Seeing the relationship as it was. Thinking about an ex's real faults, and what wasn't working, reduced feelings of love for them in an experiment by Langeslag and Sanchez (2018). It also made people feel worse in the moment, so it's something to do when you're ready.
Feeling looked after again
Underneath a lot of break-up pain is the loss of being cared for. One way to work with that directly comes from attachment therapy. The Ideal Parent Figure method asks you to imagine being cared for exactly as you needed, and to stay with how that feels. It was developed for use with a therapist, and the evidence so far is promising but early. Here's how it works and what the research shows.
Our free 10-minute session for after a break-up is based on it, with a 3-minute version for the moments when it hits hardest.
If it's more than heartbreak
Some weeks after a break-up are very hard, and that's normal. If you can't manage day to day, if it isn't easing after a couple of months, or if you're having thoughts of harming yourself, please talk to someone. Your GP or doctor is a good place to start.
In the UK you can call Samaritans free on 116 123, any time. In the US, call or text 988. In an emergency, call 999 or 911.