Linda, married for just three years, works in an office. She’s developed an intense friendship with her colleague, Dave, and now finds herself longing for him to come in every morning. Her back is to the door, she can’t turn round each time it opens but every fibre of her body is stretching towards the sound of his step. Then she can relax. She’ll turn and hail him in her heartiest voice: so matey, so innocent.

At lunchtime they’ll leave together, suggest sushi, bitch a little about their respective spouses, say they love them really, share personal hopes, fears and memories as well as work gossip, and tease each other — helpless with laughter. She’ll pick a thread off his lapel. He’ll tell her she shouldn’t change her hair because it’s gorgeous. Back in the office, chummy as ever, they’ll call their partners about food buying or visiting in-laws. That night Linda’s husband asks what she did for lunch, since she’d left the office when he called. “Oh, I looked for shoes — didn’t find what I wanted,” she’ll shrug. Dave’s wife, hoisting the toddler on her hip while the four-year-old whines, is too tired to care. Yet something will prompt his oh-so-casual fib about nipping out with Tony for a lunchtime pint.

According to numerous websites on marital problems the Emotional Affair is the latest serpent in the beleaguered marital paradise. Always tempting, always hissing the three seductive S sounds — Sharing, Sexual Attraction and Secrecy — it is inevitably dangerous and may sometimes lead to a fall. Although our couple may never end up in bed, they know in their hearts that what they’re practising is a form of safe sex, all the more powerful for being unconsummated. Linda fantasises about going away for a romantic weekend with Dave, who shares her love of art galleries, while her husband does not.

After ten years Dave feels the spark has left his marriage, loves flirting with his friend Linda, but congratulates himself on not taking it further. A relatively unsubtle creature, he thinks he’s mature because, even though quietly crazy about his colleague, his trousers are resolutely zipped up. When, of course, every woman knows it is the unzipped heart that causes the most trouble.

How do you distinguish the kind of merry flirtation, which lightens the atmosphere of the workplace, from the intense friendship shared by Linda and Dave? I’m 10 and have a crush on my big brother’s 15-year-old friend. He knows it, teases me, secretly basks in the adoration. I’m 20, meet him again, and we flirt like mad, swapping memories, which act as a curious barrier to anything else, because he can’t help but think of me as a child. The truth is, even though we think each other attractive, the crucial element of fancying is missing.

The crush derives all its power and sweetness from the fact that it’s as beyond fantasy as it’s beyond expression. The flirting is a way of responding to someone you really like, which is why you can “flirt” with members of your own sex. Flirtation is about having fun, and in most cases doesn’t progress to intensity and innuendo — which two factors are essential to the emotional affair. These relationships are driven by a restless “what if?” which sees the beloved friend as the perfect partner in another life. Overt sexual attraction is always present — all the more intense by being suggested in words or looks, not deeds. After all, a one-night stand can be deeply disappointing, whereas Mind Sex can go on for weeks, months, even years.

According to the American Association of Marriage and Family Therapy, 15 per cent of wives and 25 per cent of husbands have had extramarital sex. But if you add non-physical intimacy — in other words emotional affairs — the numbers rise by over 20 per cent. Two significant shifts in modern life may account for the sudden surge of interest in the phenomenon of the emotional affair. For one thing, the concentration on careers (as well as credit cards) encourages people to work longer hours, and so the workplace becomes more of a focus than ever. Colleagues share platonic friendships, which have the opportunity to edge into something more intense simply because of time. If both halves of a couple work hard, and their time at home is all about parenting and domesticity, they may find they’re sharing more interesting and intimate experiences with special friends at work. Once that edges into one-to-one socialising and confidences the stage is set. If you wonder whether your friendship is actually an emotional affair, the key question to ask is — am I willing to tell my partner all about it? Would he/she approve? If the answer is “No”, the chances are you’re on dangerous ground. You could also ask yourself how you’d feel if your partner was sharing the same intense confidences with somebody else. Would you count it as infidelity — sex or no sex? Which is worse, a heavy snogging session at the office party, or heavy emoting day after day?

Second, the internet cannot be left out of the equation; the biggest facilitator of emotional affairs, it enables people to zip much further along the road of intimacy even than office chat. What could take months in the office can race forward in a few weeks online, for there is a deceptive safety behind the computer screen. Escalating e-mails bounce around offices, while complete strangers start e-mailing innuendoes about their sexual tastes and prowess in the amount of time it takes a lonely couple meeting at a club to discover that they both like country music. Deceiving us that anything is possible, the web is a sticky area in which many get entangled and caught.

The glorious, problematic thing about human beings is that we are multidimensional, which is why I suspect that it’s unrealistic to think we can find The One who satisfies all our needs. I also know from experience that you can have a friendship with a truly stunning colleague, sharing deepest confidences as well as laughter, without ever slipping towards an emotional affair. People will always love the thrill of attraction, but there is always a choice about where you take it. If you value the commitment central to your life, you need to concentrate your time and energy on conserving it. And the best way to do that is with an ongoing conversation, which never shirks from the secrets of the heart.

Click here to read Mike Jackman confess to the thrill of an affair

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