It seems like the ultimate irony – the least likely outcome to an act of betrayal that for most people spells the end of a marriage. Sometimes, however, instead of causing a death blow, being caught out can end up saving it. In some cases, an affair can improve a relationship that has for years been stuck in the doldrums; it can be a desperately needed wake-up call, a chance to reflect and face painful truths. Of course, this is a high-risk strategy and many couples cannot get past the bitterness and resentment that the infidelity inevitably brings, but some can and do get through the pain of an affair and end up stronger.

Shena, 56, believes that her five-year relationship with an older married man improved her marriage in the long term. “I was very young when I married, just 19, and was used to being a ‘good’ girl, I knew nothing about sex at all. My husband was Catholic and, although older than me, he knew scarcely any more. So things in the bedroom were rushed, unsatisfactory and occasionally even painful.”

With three small children, Sheena could not go out to work so took on piecework at home and started an affair with the man who delivered the materials and oversaw her work. “I was able to learn things from my lover – who was much more experienced – and gradually, I’d introduce these techniques with my husband.”

Fortunately, her husband never found out, although she admits that over the years she did have a couple of scares. “I was involved in a minor car accident once, on my way back from my lover’s house. There was no reason why I should have been in that part of town and knowing that I could have been found out brought me back to my senses. My children were older, I’d started full-time work and my confidence had grown, so there was no reason to continue. I cooled it and we drifted apart.” Twenty-five years later, Sheena describes her marriage as “very happy”.

“It was find ’em, bed ’em, leave ’em”

For Martin, 42, infidelity was used as a safety valve during his 18-year marriage.

“My wife was never that interested in sex, but after the birth of our youngest daughter she seemed to go right off the idea. I loved my children and I loved my wife, but it was like a one-way street. I was expected to work my butt off but nobody thought of my needs.” He has had several affairs over the past ten years. “The affairs kept me sane. My children had both their parents and were doing well at school. My wife had a lovely house and I was happy too. Sex is like a bodily function. It doesn’t mean much.” Martin met the women he had affairs with while travelling for his job: “I might see some more than once, generally it was find ’em, bed ’em and leave ’em.” In effect, his affairs were a sticking plaster to keep his marriage intact. Unlike Sheena, he learnt nothing from his unfaithfulness. Worse still, he did not know when to call it off.

Five years ago, when Martin was promoted, he had less opportunity to travel and started to use an internet dating site for married people. “With this woman it was really special. I don’t think I loved her, but I really liked her and I got careless.” He failed to delete an explicit text and was found out. Josie, his wife, hadn’t seen it coming. “OK, things were not perfect in bed, but we sort of muddled through; at least I thought we did. We’d make love, perhaps only every three or four months, but that’s only natural after you’ve been married for so long. What makes me the angriest is that Martin didn’t tell me how he felt.”

Although discovering that your partner has been unfaithful is extremely painful, once the shock has worn off, some may discover unexpected side-effects. Without the urgency and drama of adultery, most couples prefer not to look too deeply at their relationship and blame tiredness or work stress for their problems.

Josie refused to be fobbed off and kept plugging away for answers about her husband’s affair: “Martin would lose his temper and complain that I kept harping on about the past, but if I didn’t find out why it happened what was to stop it happening again?” Eventually, she was forced to look at their sex life, something she doubts she would have done without the spur of the affairs.

The second benefit of being found out is that both partners become angry, let their guards down and all the hidden and unacknowledged problems are uncovered. In the case of Martin and Josie, it became clear just how hard he found it to express his emotions. “I’m cold. It’s inherited, all my family are the same,” he said.

When Carl, 32, started his affair, he had no lofty reasons, such as saving his marriage. He met the other woman when they both collected their children from school. “I never set out to cheat. One day Amanda phoned me at work and asked me to come over to her house. I kind of knew that it would not be about the children. One thing led to another and we ended up kissing on the sofa.” When Carl’s wife, Sofia, found out, she was devastated. “I thought we had the perfect marriage,” she said. She was particularly upset because Carl could not explain why he had cheated. In counselling they began to dissect the relationship. While on the surface, they had a good marriage, they had both been hiding small hurts to keep the other happy.

When they finished counselling, Sofia concluded: “When I found out about Carl’s affair, I thought it was the worst thing that could ever happen, but we’ve learnt so much. I wish the affair had never happened, but in the long-term it has probably been good for us.”

Eventually, Josie decided that Martin, unlike Carl, was not going to change. He still wanted to save the relationship, but as she said, “too much water was under the bridge”.

So if you have been tempted to have an affair, have been flattered by the attention of a colleague or have begun talking intimately with someone who isn’t your partner, it would be better to recognise the signs that something is missing in your relationship and work on it. There might be unexpected benefits to the discovery of an affair, but the negatives – betrayal, jealousy and desire for revenge – can overwhelm everything else.

— Andrew G Marshall is a marital therapist and author of I Love You But I’m Not in Love With You (Bloomsbury £8.99)

First aid for your marriage

Have an affair with your partner. Psychologists at British Columbia and Virginia universities discovered that we treat strangers better than our partners.

Why not meet your partner in a bar, pretend to be strangers and chat each other up. Afterwards, act like cheating lovers and book a hotel room in the afternoon.

Why not undertake a challenge together, such as rock climbing or parachuting from a plane?

Develop good habits. Small, repeatable changes to your routine – eating together in the evening or switching off the TV one night a week – can make a big difference.

See your partner in a new light.
Distance and closeness keep attraction alive. Watch your partner give a presentation or play sport. It will show you are interested in every aspect of his or her life.

Find an all-consuming joint project: renovate a house or start a business.

— Andrew G. Marshall is the organiser of Adultery in the UK, a survey to discover what helps and what hinders recovery.
To take part, go to www.andrewgmarshall.com

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