Too often, affairs are seen as the outcome of random horniness or just plain old nastiness, but that’s very rarely the case. When it comes to affairs, we spend far too long being incensed or secretive and far too little time trying to understand. In truth, affairs stem from a very fiddly aspect of our romantic psychology. In relationships with a partner, all of us need carefully calibrated mixtures of two different ingredients. We have a need for closeness and a need for distance. We want to impart closeness: to feel we can hug, touch, be cosy, intimate and entirely relaxed and at home with someone. We want them to know our thoughts and to wander freely in their minds too. But we also need distance enough not to feel cloyingly submerged, subsumed or owned by another. We want to retain a sense of freedom, we need a private room to which we alone have the key. Any imbalances towards over-closeness or over-distance may prove catastrophic if left unaddressed. In a relationship which threatens to lean perilously towards over-closeness we can be driven to strain a powerful urge to prove to ourselves that not everything we do and are is owned by the partner, that we remain desirable to the world and a going concern in and of ourselves. Going to bed with a new person might not simply be about lust, it’s about escaping the alarming feeling that one’s whole identity appears to be on the verge of dissolving into the couple. But too much distance can undermine fidelity no less powerfully. The distance reads like constant rejection: when we try to touch the partner, they move away or sigh. When we bring up something personal, they change the subject. We may end up having an affair not because we don’t love the partner anymore, but precisely because we do. And yet the distance they appear to be imposing on us, through their lack of engagement, feels unendurable and humiliating. It’s the final irony, but if caught would be accused of not caring, when it was caring too much that might have inspired the whole mistaken escapade. Tragically, two people almost never enter a relationship with the same needs for distance or closeness, that’s why in every couple we hear the accusation that one person is too clingy and another is too cold. These are unhelpfully vicious words for what are, at heart, just two different ways of feeling comfortable in love. It’s therefore an early imperative in any relationship to work out what the relative needs for distance and closeness actually are to air the disjuncture not to get angry about it, and mutually and with good humour to apologise for ones distinctive contribution to it. Only thus can we hope to ensure that the gap won’t lead in an online chat, at a bar or at a conference to a situation where only an affair feels like a plausible solution to the vexing problems of distance and closeness.