If there's one theme that I regularly hear from those who've been unfaithful to their partners it's that, at the time, their affair seemed so right, but with hindsight it ended up feeling so wrong.

It's staggering how powerful illicit passion can be in convincing a person that their behaviour is acceptable. A guilty conscience usually tries to justify what it's doing as a salve: it's a type of defence mechanism to deny that your actions could be bad. Owning up to that harsh reality could take the zing out of the fling, which defeats the underhand purpose.

For example, if you keep telling yourself that you've been taken for granted, or your partner doesn't love you any more, you begin to believe your own PR.

Emily, 29, did just that when having a fling behind the back of her partner Jasper. As she repeated her mantra to her closest confidants - that Jasper cared only about his work and not her - she came to believe that she'd every right to the affair. She defended this position for six months.

Aunt Sally: I want to apologise to my boyfriend’s ex for our affair

Two years ago, I had an affair, which resulted in us both being divorced by our spouses

BACKGROUND

• My lover has a girlfriend and kids

• Should I leave my husband for my lover?

• Should I end my affair for cheating fiance?

When I met her it was beginning to wear thin. A turning point had come when Jasper raised how sad it made him that they'd “grown apart”. Boy, did she feel guilty. Not only had the passion in the affair burnt itself out, but Jasper was showing himself to be a really good guy who acknowledged his mistakes.

Emily had come to see me to discuss communication strategies for her job, but having let spill about her private life instead, she decided to try to develop effective communication with Jasper. First she had to face the music and hope that he would forgive her. The latest news was that he had.

Anyone in Emily's position needs to communicate effectively for any chance of salvaging their mess. It's imperative to consider what you'll say rather than steaming in because you want to get it over with. Select key phrases carefully so that they're tactful and demonstrate remorse. Choose a time to own up when you won't be interrupted; it's important to be prepared for the worst possible reaction, and show determination to make amends, staying calm, say, while your partner rails at you.

Having the patience of a saint to go over details, repeat your apology and your reasons and to ask for forgiveness willhelp you through the coming weeks.

If only people could predict how they'd eventually feel (laden with guilt that they can't simply airbrush away) it may just prevent some affairs. But many are prepared to leap at what feels right not realising how wrong it'll be.

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