From YouTube beef to Twitter feuds, nemeses are trending in real life. So why do we have them? “Our nemesis often shows what actually matters to us. They reflect back our own values and ideals,” says psychologist and life coach Honey Langcaster-James. “It’s often someone who is doing what we would secretly like to. Or perhaps they appear to be living their life in a way that we aspire to. Your nemesis is a mirror, reflecting back what you want to be doing with your life.”

We tend to pick nemeses that are quite similar to us. They are us but with a better CV, #friendshipgoals and great hair (how do they do that?). Social media puts all of this pettiness in the palm of our hands.

Yet nemesis-collecting can be a noble pursuit. We pick workplace nemeses according to how willing they are to throw others under the bus, Totaljobs found, suggesting we’re keen to protect colleagues who have been wronged. There are other good reasons for having an adversary. Long-distance runners cut five seconds off their race times when competing against an arch-rival, according to a 2014 study from New York University. Nemeses are motivational.

“Think of a nemesis as grit in your oyster,” Langcaster-James suggests. “They might really wind you up, but they also might represent something that is against your own values. They can make us think, ‘What do I want to be doing more of? How should I be investing my time?’ You can use your nemesis as a springboard to differentiate yourself from. You can even turn a nemesis into an inspiration.”

Here, four women offload about their arch-nemeses.

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