I’m having a bit of an existential crisis. According to new research, if I’m anything like the average person, around half the people I consider my friends don’t consider me theirs in return: that’s how chronically bad we are at judging the reciprocity of friendship. Of course, I already knew lopsided friendships existed; I’ve got several, and I’m sure you have, too. But in every case I can think of, it’s me who’s not especially invested, and the other person who doesn’t realise it. I’m not supposed to be the desperate one. Yet if studies such as this are correct, the phenomenon is so widespread that it’s highly unlikely I’m an exception. As with the famous finding that almost everyone thinks they’re in the top 50% of safe drivers, we can’t all be the ones with an accurate sense of who really likes us.

And if we’re stumbling through life with such a distorted understanding of our social circles, where does that leave all the other received wisdom about friendship’s importance? It has been found that friends keep us physically healthy, alive for longer, less vulnerable to depression and more financially successful – but how much of that, especially when the research is based on self-reports, comes from actually having friends, versus believing that you do?

It also makes you wonder if there’s a friendship version of that old (and true) observation about romance: that in any relationship, the person who cares about it the least controls it the most. Are we shackled to our lopsided friendships because we intuit that the other person still needs to be persuaded that it’s worth hanging out with us?

Perhaps it shouldn’t be surprising to learn that, when it comes to friendship, we’re in the grip of an ego-boosting delusion: that’s true in many domains of life. People with healthy self-esteem habitually overestimate both their interpersonal skills and their control over events; some psychologists argue that mildly depressed people have a more accurate grasp of their abilities than the non-depressed. To thrive in the world, it’s often more useful to feel good about yourself than it is to see things as they are.

Oh, and one more reason not to freak out over the thought that your “friends” might secretly not like you: this particular study, as with so many in social psychology, focused on university students (and their friends and young family members). It’s well-known that our social circles shrink as we mature, too often culminating in a friend-starved old age. But isn’t it possible that this shrinkage is better thought of as a winnowing, as we zero in on those friendships that are actually reciprocated? There are certainly reasons to worry about a loneliness crisis among the elderly, but having only a few friends may not be good evidence for it. If I make it to my final years with only a handful of friendships, because life has filtered them down to the ones that really count, I’m not sure I’d call that a sad state of affairs. I’d call it an efficient use of my remaining time.

oliver.burkeman@theguardian.com