Q A gay colleague helped me while I was working late one evening. I said, in mock gratitude, “I could kiss you”, to which he replied, “Why not?” Soon we were engaged in a sexual act. I feel very excited whenever I look back on the incident. Should I start a relationship with him, or try visiting a gay bar to find out whether this is what I really want, before discussing it with my wife? Or should I view the episode as a one-off?

A Before we deal with the issue of your sexuality, I would like you to consider how you would feel if your wife “accidentally” had sex with one of her work colleagues and subsequently felt conflicted by a choice between (a) establishing a relationship with the man with whom she had sex, or (b) secretly experimenting with other men in order to establish whether she was (c) 100 per cent certain that she did, or didn’t, want to have sex with you any more. Harsh, isn’t it? Cheating is cheating, regardless of whether it is with a member of the same sex or of the opposite sex, and your confused sexuality does not excuse selfish or insensitive behavior.

Same-sex experimentation is pretty common. Research at Harvard School of Public Health in the US in 1994 found that 20.8 per cent of men and 17.8 per cent of women admitted to same-sex sexual behaviour at some point.

While one homosexual experience doesn’t define anyone as gay, a married man who re-evaluates his sexual identity as the result of a brief encounter can be sure that he isn’t completely heterosexual. Many men and women successfully ignore sexual attractions to people outside their marriage, but if the events you describe were just a one-off sexual experiment, you wouldn’t now be contemplating clandestine trips to gay clubs. Let’s face it, if you were incontrovertibly heterosexual this probably wouldn’t have happened in the first place, since total sobriety and a wife waiting at home would usually be more than enough to deter the average man from engaging in an impromptu sex act with a gay work colleague.

Your insistence that this event was not premeditated is somewhat reminiscent of the man who turns up in A&E having “slipped in the shower” and mysteriously lost a shampoo bottle, but it is true that sexuality doesn’t necessarily remain static and some people discover that they are attracted to men and women later in life. The Klein Sexual Orientation Grid uses seven component variables of sexual orientation to describe a person’s sexual proclivities, based on their past, present and ideal sexual disposition. Taking the test online (bisexual.org/kleingrid.html) would help you to gauge how much your behaviour, fantasies, emotional preferences, social preferences, lifestyle and self-identity may have shifted away from heterosexuality.

Growing acceptance and positive role models in popular media have helped to destigmatise homosexuality, but “coming out of the closet” as a married man is still no picnic, and, weirdly, for a man to declare himself bisexual seems even more problematic — there are almost twice as many bisexual women (2.8 per cent) as men (1.8 per cent) in the population.

The psychologist Beth Firestein speculates that this may be because male bisexuals feel “pressured to label themselves as homosexuals instead of occupying a difficult middle ground in a culture that has it that if bisexuals are attracted to people of both sexes, they must have more than one partner, thus defying society’s value on monogamy”.

Right now you see only two options for yourself: to forget what has happened or to explore a possible gay identity in secret. But there is, in fact, a third way. Honesty is never the easiest option, but if you were to bite the bullet and explain what has happened to your wife, your “tremendous excitement” would be exposed for what it really is — a messy and difficult lifestyle choice with widespread implications for you and her.

While that truth might not necessarily set you free, it would set your wife free and allow her to make an informed decision about what she wants and deserves from her marriage.

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