Being cheated on is the sort of painful experience which not only lingers, but also can inform and influence the behaviour and feelings someone takes forward into their next relationship.
Yet for something so disruptive and detrimental, it is also pretty common. 45 per cent of British men and 21 per cent of British women have admitted to straying . The dialogue and image around infidelity have also shifted recently. Not only is cheating (or the motivation behind it) likened to a 'grey area', but it's also big business - think ' Ashley Madison '.
Whatever drives people to do stray, it's clear there is no one definitive stimulus.
But researchers have been able to put an 'age' on when someone is most likely to cheat.
The danger years
According to research conducted by infidelity website, IllicitEncounters , this age is 39 years old, reports Mamamia .
At this age, people are TWICE as likely to cheat on their partners than at any other age. It's not just '39' either - 29 and 49 were also cited as other 'danger years', although to a lesser extent than 39.
There is research substantiating this figure.
Across six studies, Adam L. Alter and Hal E. Hershfield from the Universities of New York and California respectively, found towards the end of each decade, people become more preoccupied "with aging, and were more likely to wonder whether their lives were meaningful."
The researchers said these concerns lead to behaviours that "suggest a search for, or a crisis of meaning" - such as an affair. The findings continued by suggesting, "This could lead to a rise in behaviors that 'suggest a search for, or a crisis of meaning,' such as an affair." What they also took pains to point, however, was that infidelity is difficult to study because - shocker - it's difficult to find willing and open participants.
And the study is not the most accurate metric - it was commissioned and backed by the IllicitEncounters after all. So don't preoccupy yourself unduly if you're partner's approaching their 39th birthday.