Have you ever been told to just "get over it" post break up? Easy for people to say but that doesn't make it any easier to do. “There might be a tendency in the public to overestimate the ease at which we should move on from failed relationships,” says Brian Boutwell, Ph.D., the coauthor of a recent study about breakups and an associate professor of criminology and criminal justice and associate professor of epidemiology at Saint Louis University. “Some people will be quite good at [splitting], and others will not. As a result, understanding that some people will simply have a naturally harder time getting over a breakup is important. Someone who has a difficult time moving on is not suffering from some type of moral failure—rather, they may simply lack the same capacity that others have to move on to a new relationship.” Here are all the other things you should know about the science behind breaking up. Call it nature. Men are more or less programmed to dump you if you cheat on them according to a study Saint Louis University. “Sexual infidelity posses a direct threat to the genetic fitness of a male,” says Boutwell. “In other words, it means he may end up raising a child who is not his own. This would mean that his own genes are not passed along.” Obviously women don't have to worry about whether or not their baby belongs to them. “However, a father present may have been critical to the safety and prosperity of the mother and her child,” says Boutwell. “Should a male become unwilling—because he fell in love with someone else, potentially—to provide for his offspring, it may be best for the female to move on to someone else.” None of this means that women are okay with cheating, it is more that an emotional affair poses a bigger threat because it could mean him leaving his family for another. Jerks are single for a reason. “A partner who is unpredictable, cruel, and violent toward a partner and their children is unlikely to represent a safe bet in terms of reproducing and raising children to adulthood,” says Boutwell. Evolutionary scholars have found that partners who are chronically violent are less likely to have children because they are unable to find sexual partners as easily. A study published in the journal Family Relations found that fighting about finances is the top predictor of divorce and it apparently holds true regardless of debt, income or net worth. These sorts of arguments were found to be longer and more intense than other types of fights. Scientists believe this is because fights about money reflect the deeper issues in a relationship. Sounds counter-intuitive but it can actually really help speed up your recovery. A new study published in Social Psychological and Personality Science found that those who ruminated over their ex ended up having a stronger sense of themselves as a single person. Uh-oh. According to a study in the journal Cyberpsychology, Behavior and Social Networking, excessive Facebook use can damage your relationship. It has been linked to emotional and physical cheating, break up and divorce. The same goes for Twitter. The researchers didn't look at why social media might be linked to these outcomes but experts speculate that it provides more opportunities to cheat and increased access to old flames. Research has shown that falling in love has a lot in common with a drug habit and as such, it is hard to break. “The regions of the brain which are implicated in feelings of love and attraction are also implicated in addiction to various illegal drugs,” says Boutwell. “This is perhaps not surprising, though, given the strong addictive feelings we feel toward someone when we fall in love with them—or when we’re broken up with and still care for our former partner.” Next time someone tells you to just move on, cut yourself some slack. It isn't easy to do. Science backs you up.