Researchers at St. Louis University found that people are hardwired to overcome heartbreak and rejection and move onto new relationships.
The researchers examined the process of falling out of love and breaking up which they call "primary mate ejection" and moving onto a new romantic relationship which they call "secondary mate ejection".
Dr Brian Boutwell, Saint Louis University, said, "'Our review of the literature suggests we have a mechanism in our brains designed by natural selection to pull us through a very tumultuous time in our lives. It suggests people will recover; the pain will go away with time. There will be a light at the end of the tunnel."
The researchers said, men and women break up for different reasons. For example, men are more likely to end a relationship because women cheated on them. That is because for evolutionary reasons, men are wired to try and avoid raising children that aren't genetically their own.
"Men are particularly sensitive to sexual infidelity between their partner and someone else. That's not to say women don't get jealous, they certainly do, but it's especially acute for men regarding sexual infidelity," said, Dr. Boutwell.
Women are more likely to end a relationship if her partner has been emotionally unfaithful. Women have been evolved to value the resources that their mates provide, such as help in raising or physical protection. They tend to reject mates who threaten to take these resources away.
Sometimes both men and women end a relationship for the same reason, for example, neither gender tends to tolerate or value cruelty on the part of their partner.
Brain imaging studies of men and women who claimed to be deeply in love also provided important clues about dealing with breakups. MRI scans showed an increase in neuronal activity in the parts of the brain like the pleasure areas which also becomes active with cocaine use.
Dr Boutwell said falling out of love might be compared to asking a cocaine addict to break his or her habit.
"If we better understand mate ejection, it may offer direct and actionable insight into ways in which couples can save a relationship that might otherwise come to a stultifying and abrupt halt," Dr. Boutwell concluded.
The study was published in the Review of General Psychology journal.