Science hasn't found a way to stop your heart being broken (yet), but it can at least tell you when it might happen.
If that's any consolation.
Psychologists call it the 7-year itch. If the name sounds overly simple, that's because it is.
A study in the The Journal of Sex Research investigated cheating in 423 participants.
Though it found that women were indeed most likely to cheat six to ten years into their relationship, men appear to hang on a bit longer and were most likely to do the dirty after 11 years.
Though the study was based on questionnaires rather than real-life outcomes, it still gives in an insight into when our relationships are at their most vulnerable.
Research from Illicit Encounters even suggests there's a day of the year your partner is most likely to cheat.
It calls 18 November 'Unfaithful Friday' based on the results of a survey it conducted with 300 users.
Apparently 72 per cent the men surveyed admitted using the 18 November as a day to enjoy another partner.
This seems to be because Christmas leaves very little time for extra-marital affairs, though you would hope it's also to do with the guilt induced by family time.