That feeling of rage and annoyance mixed with despair you get when you're scrolling through Facebook and see one of your friends on holiday or doing something fun is real, and it's having a bad effect on you.
Researchers at University of Missouri investigated what exactly the effects were for Facebook users, and they found that feelings of envy and depression were triggered by use of the social media networking site.
The problem was mainly limited to those who use Facebook for keeping an eye on what their friends do, or perhaps an ex-partner, which is generally referred to as "stalking" by the kids these days. Speaking about the findings, Margaret Duffy, professor of strategic communication at the MU School of Journalism said "we found that if Facebook users experience envy of the activities and lifestyles of their friends on Facebook, they are much more likely to report feelings of depression".
The things that triggered those feelings more often than not were posts from couples about how in love they were, pictures of people's kids and how great they are, or those holiday snaps where your friends are off sunning themselves on some exotic beach, and you're stuck in the rain and cold, with the wind threatening to rip your face off.
The good news is that if you're not using Facebook for "surveillance", then you won't experience the unpleasant symptoms associated with this study, so stop stalking your ex and go do something that's not using a screen, since it's probably the reason you can't sleep properly.