According to Gallup poll, 90% of Americans say infidelity is immoral, and 65% say it is unforgivable. Yet, despite the negative judgement society places on cheaters, infidelity occurs in 30–35% of marriages.

According to numerous studies, it is usually the male who strays, and most often with unmarried female partners. In fact, compared to 25% of women, a stunning 50% of men have or will cheat, and 85% of these affairs will be with single women. Though we can assume these men are not looking for new wives, since less than 10% of these affairs end in marriage to the affair partner.

One might wonder why the disproportionate numbers. Boy meets girl. They select one another as life partners. What goes wrong that leads to boy to stray? There is a considerable body of research into this very question emanating from the fields of psychology, sociology, marriage and family therapy, and life coaching. 

• Men are better able to separate love from sexual activity
• Men have a greater desire to experience sexual infidelity.
• Men are more willing to engage in behaviours such as planning, lying, and cover-up involved in infidelity.

More provocative, is the question, what specific personality factors lead to the above three findings? The field of personality studies has revealed some interesting trends emerging from studies into particular personality traits.

Unlike attitudes, beliefs, and states that can change with circumstance and experience, personality traits are relatively stable throughout one’s life. Examining the personality traits of those who report engaging in infidelity has helped identify key trait factors associated with the occurrence of extra-relationship sexuality.

The Big Five personality traits are five well-standardised broad domains used to assess personality . Here we explore the findings associated to each, in regard to the likelihood of infidelity.

Extraversion

This trait is related to positive affect, for example happiness, and self-esteem, and is associated with sociability, dominance, and active or energetic traits. Sounds great, right? However, those high in extraversion have also been found to have lower rates of relationship exclusivity, more favourable views toward multiple sexual partners. and are more willing to experiment with new and/or risky sexual activities.

It is possible that those high in extraversion attract potential partners as a result of their socially dominant and assertive traits, making it easier to participate in extramarital opportunities through the simple fact that they attract greater numbers of possible partners.

Agreeableness

This trait is also linked to infidelity, or shall we say the lack of it is. Multiple studies indicate that individuals who engage in extra-marital relationships tend to be disagreeable, generally uncooperative, deceitful, non-empathic, and lacking in trust.

Conscientiousness

This is another trait that is negatively associated to infidelity. Those who report infidelity tend to be disorganised and unreliable, or low in overall conscientiousness.

Openness to experience

This is perhaps the least researched aspect of the comprehensive Big Five model. Openness captures intelligence, creativity, curiosity, perceptual ability, and insightfulness. Those high in openness tend to expose themselves to novel, unconventional, and challenging thoughts, sensations, and experiences, and they are generally independent in their judgements and enjoy breaking away from norms.

Yet those high in openness are more likely to report infidelity, lower relationship satisfaction, less commitment to their romantic partner, and take part in risky sexual behaviours including infidelity.

Neuroticism

This trait lights up in the data more than any of the above traits. Neuroticism is characterised by a lack of positive psychological adjustment, low emotional stability, and poor regulation of emotions. Those high in neuroticism have less impulse control, are generally less happy in their relationships, and are more emotionally insecure than are those who are low in this trait.

Where do we go from here?

What advice can be given to boy and girl as they approach what is hoped to be a lifelong commitment? Certainly, it is completely unreasonable to advise girl not to marry boy simply because he is friendly, occasionally grumpy, lacks organisation but enjoys new experiences, and gets a little emotional from time to time. In fact, this might be exactly the sort of man she’s attracted to. And he may never stray – although he is more likely to.

And what advice can be given to boy, as he prepares to avow lifelong commitment, and (though these specific words may not appear in the vows) sexual exclusivity. According to personality trait theory, he’s not going to change.

And what of the many women who will be attracted to this grumpy, disorganised, overemotional, friendly guy over the years to come? What advice have we for them? Well we could warn her that only 50% of affairs that are revealed end in divorce, and that less than 10% result in the marriage of the affair partners.

Infidelity stings

But, perhaps the very best advice for all, is that infidelity stings. It hurts to find out the love of your life has been unfaithful. It hurts to see the woman you love crushed by your actions, and it hurts to involve others who win this three-way battle less than 10% of the time. And, we might go on to advise all parties that their children will suffer too.

Children of parents struggling through infidelity receive less parental regulation for emotional support, and may tend to have difficulties learning to self-regulate their own emotions. Instead, of self-regulation, these children tend to develop negative emotions such as distress, anger, and anxiety.

Additionally, they are at increased risk of developing poor behavioural coping strategies such as drug use, risky early sexual behaviour, and generalised acting out. Sadly, these effects may take place even when infidelity is not revealed in the home, as children are so keenly tied to parents for care and guidance, that they respond to even subtle alterations in parental affect.

Conclusion

When children do have knowledge of an extramarital affair it causes changes in the way they communicate with others in their own relationships with adults and peers, ultimately leading to poor communication skills and poor boundary-setting.

We might also warn boy, girl, and potential affair partner that children dealing with a loss or separation related to parental infidelity are more likely to develop insecure attachment styles, and there is significant evidence indicating that they will struggle with all forms of interpersonal relationships throughout their lives.

Unfortunately, though all of society is aware of cheating, few are aware of the sad findings presented here. It is said that knowledge is power. When friends, co-workers, and relatives confide in you, share these statistics. Talk to your spouse, talk to your friends, and talk to your older children about the risks and damaging effects of infidelity.

Dr Carmen McGuinness is a Board Certified Behaviour Analyst, and health psychologist, specialising in children with disabilities, attachment, and family trauma.