The stories we read and love as children are almost all about friendship. Surveying the costumes at my kids' school on World Book Day recently, I saw wizards, packs of forest animals, miniature pirates: all of them heroes and heroines of collective adventures. The books they celebrated overwhelmingly concern the escapades, fallings-out and devotion of friends, furry or otherwise.
Now consider, by contrast, the stories we read as adults. Friendships rarely feature in the foreground - vanishingly rarely, in the case of friendships between men.
Bromances and buddy dramas are rife on television and in the cinema, often involving cops or cowboys or some other embattled duo who rely on each other for survival. But grown-up novels: not so much. Friends, when they intrude, tend to be marginal members of the supporting cast, the main events generally concerning romantic love and families, sex and death.
In part, this ousting of friendship from the story reflects the ways our lives evolve as we grow up. When we are very young - like Christopher Robin in Winnie-the-Pooh - our friends are at the centre of our comfortingly small worlds. Making friends is among the first autonomous choices that tiny children make: friends are among the first things in their lives that are truly their own. Meeting, enjoying and losing them are among our most important and intense infant experiences.
In adulthood, the hierarchy of our relationships and the distribution of our time drastically shift. Rendezvous with friends we once saw every day in classrooms and playgrounds seem inessential in the crush of work and family. Our get-togethers become ever more infrequent, until we wind up seeing them every few weeks and then, as we tip over into middle age - and when we make a special effort - a few times a year. Instead of exchanging hushed confidences in claustrophobic bedrooms, we trade functional text-message updates and, very occasionally, when the bill-paying and taking out of recycling permits, talk hurriedly on the phone. We switch them off if they call at the wrong moment, intending to ring them back. Too often, we don't.
So maybe it isn't surprising that other relationships tend to preoccupy modern authors (19th-century ones, such as Mark Twain and Jane Austen, were more interested in friendship, perhaps because relations between the sexes were more circumscribed then, leaving more time and space for friends).
It doesn't help that the power and chemistry of friendship are trickier to evoke than the obligations of family or the tingle of infatuation. Depicting why two unrelated adults might choose to invest time and feelings in each other, for no reason other than that they like each other, is a hard writerly task - just as, sometimes, the commitments we make to our friends can be hard to rationalise to ourselves. "No money, no sex," thinks Adam, one of the two male friends at the heart of my new novel, The Faithful Couple. "Friendship was a luxury in any utilitarian calculus."
And yet, without it, Adam reflects, "life would be thin." We see our friends less and less as we get older, but many of us, I think, come to rely on them more and more - because, sometimes even more than relatives and spouses, they understand our dilemmas and decisions, and because, as our acquaintances age, ever more of our past is stored in them. Marginal as they come to seem in our crowded adult lives, our friends actually become all the more indispensable.
Just as important, from a novelist's perspective, is that all old, deep friendships are intriguingly paradoxical, and intrinsically dramatic. We rely on our oldest friends to tell us harsh truths - but also to tell us compassionate lies. We celebrate each other's successes but also, often, sneakily envy them. We love our friends, and rely on them, but also resent them, and sometimes let them down. All longstanding friendships are dynamic, as power and status ebb and swirl. They all have their grudges and crises, betrayals and reconciliations, just as romantic relationships do.
In The Faithful Couple, I've tried to convey a fascinating tension that I think lies at the heart of many enduring friendships. Our closest friends know things about us that no one else does, often not even our spouses. Thus, in a way, every friendship is a kind of conspiracy, of the friends against the world. But because we know our friends' secrets, and they know ours, we are locked together in a kind of two-way blackmail that is its own complicated bond.
Friendship, I think, is too vital and gripping a theme to be left to children stories.
