There are some couples who take pleasure in together selecting a third person, a stranger, to have sex with one of them while the other watches. The voyeur willingly cedes his or her rightful position and derives erotic enjoyment from bearing witness to the induction of his or her spouse. This is not an act of altruism. Rather, the new actor has been brought in for a particular purpose: to remind the voyeur of what is arousing about his or her partner. The voyeur uses the stranger’s lust as a map to trace the way back to desires long obscured by the fog of routine. Through the agency of the stranger, the voyeur can feel the same excitement for a partner of twenty years as on the night they first met.

A less threatening and less dramatic version of this act of perception is readily available by checking in to a hotel room for a night. Our failure to notice the erotic side of our partner is often closely related to the unchanging environment in which we lead our daily lives. We can blame the stable presence of the carpet and the living-room chairs for our failure to have more sex, because our homes guide us to perceive others according to the attitude they normally exhibit in them. The physical backdrop becomes permanently coloured by the activities it hosts – vacuuming, bottle feeding, laundry hanging, the filling out of tax forms – and reflects the mood back at us, thereby subtly preventing us from evolving. The furniture insists that we can’t change because it never does.

Hence the metaphysical importance of hotels. Their walls, beds, comfortably upholstered chairs, room-service menus, televisions and small, tightly wrapped soaps can do more than answer a taste for luxury; they can also encourage us to reconnect with our long-lost sexual selves. There is no limit to what a shared dip in an alien bath tub may help us to achieve. We may make love joyfully again because we have rediscovered, behind the roles we are forced to play by our domestic circumstances, the sexual identities that first drew us together – an act of aesthetic perception that will have been critically assisted by a pair of towelling bathrobes, a complimentary fruit basket and a view out of a window onto an unfamiliar harbour.

The common conception of anger posits red faces, raised voices and slammed doors, but only too often it takes on a different form, for when it doesn’t understand or acknowledge itself, it just curdles into numbness.

the specific incidents that anger us happen so quickly and so invisibly, in such fast-moving and chaotic settings (at breakfast time, before the school run, or during a conversation on mobile phones in a windy plaza at lunchtime) that we can’t recognize the offence well enough to mount any sort of coherent protest against it. The arrow is fired, it wounds us, but we lack the resources or context to see how and where, exactly, it has pierced our armour.

We may, for example, be deeply wounded when our partner fails to notice our new haircut or doesn’t use a breadboard while cutting a bit of baguette, scattering crumbs everywhere, or goes straight upstairs to watch television without stopping to ask about our day. These hardly seem matters worth lodging formal complaints over. To announce, ‘I am angry with you because you cut the bread in the wrong way,’ is to risk sounding at once immature and insane. An objection of this sort may indeed be both of those things, but given that immaturity and insanity by and large constitute the human condition, we would be well advised to stop subscribing to (and then suffering from), any more optimistic notions.

To fall in love with another is to bless him or her with an idea of who he or she should be in our eyes; it is to attempt to incarnate perfection across limitless range of activities, stretching from the highest questions how to educate the children and what sort of house to buy) to the lowest (where the sofa should go and how to spend Tuesday evening).

By overwhelming consensus, our culture locates the primary difficulty of relationships in finding the ‘right’ person rather than in knowing how to love a real – that is, a necessarily rather unright – human being. Our reluctance to work at love is bound up with our earliest experience of the emotion. We were first loved by people who kept secret from us the true extent of the work that went into it, who loved us but didn’t ask us to return affection in a rounded way, who rarely revealed their own vulnerabilities, anxieties or needs and who were – to an extent, at least – on better behaviour as parents than they could be as lovers. They thereby created, albeit with the most benign of intentions, an illusion that has complicated consequences for us later on, insofar as it leaves us unprepared for the effort we must legitimately expend to make even a very decent adult relationship successful. We can achieve a balanced view of adult love not by remembering what it felt like to be loved as a child but rather by imagining what it took for our parents to love us - namely, a great deal of work.

Our feelings of anxiety are genuine but confused signals that something is amiss, and so need to be listened to and patiently interpreted – processes which are unlikely to be completed when we have to hand, in the computer, one of the most powerful tools of distraction ever invented. The entire internet is in a sense pornographic, a deliverer of a constant excitement that we have no innate capacity to resist, a seducer that leads us down paths that for the most part do nothing to answer our real needs. Furthermore, the ready availability of pornography lessens our tolerance for the kind of boredom that grants our mind the space it needs to spawn good ideas - the creative sort of boredom we may luxuriate in during a bath or on a long train journey. Whenever we feel an all but irresistible desire to flee from our own thoughts, we can be quite sure there is something important trying to make its way into our consciousness – and yet it is precisely at such pregnant moments that internet pornography is most apt to exert its maddening pull, assisting our escape from ourselves and thereby helping us to destroy our present and our future.

A portion of our libido has to be forced underground for our own good; repression is not just for Catholics, Muslims and the Victorians, but for all of us and for eternity. Because we have to go to work, commit ourselves to relationships, care for our children and explore our own minds, we cannot allow our sexual urges to express themselves without limit, online or other-wise; left to run free, they destroy us.

The fact that the straying spouse has had the temerity to imagine, let alone act on the idea that it might be of interest to push a hand inside an unfamiliar skirt or pair of trousers should not truly come as such a surprise after a decade or more of marriage. Should there really be a need to apologize for a desire that could hardly be more understandable or ordinary? [Rather] than ask their betrayers’ to say they are sorry, the ‘betrayed’ might begin by saying sorry themselves - sorry for being themselves, sorry for getting old, sorry for being boring sometimes, sorry for forcing their partners to lie by setting the bar of truthfulness forbiddingly high and (while we are at it), sorry for being human. It can too easily seem as if the adulterous spouse has done everything wrong, and the sexually pure one nothing. But this is an abbreviated understanding of what wrong entails. Certainly adultery grabs the headlines, but there are lesser, though no less powerful, ways to betray a partner, including not talking to him or her enough, seeming distracted, being ill-tempered or simply failing to evolve and enchant. […] A spouse who gets angry at having been betrayed is evading a basic, tragic truth: that no one can be everything to another person.