One of those married folks dating sites (along the lines of The Ashley Madison Agency) thinks they've chipped away at the Infidelity Mystery and deduced (yet another!) reason why people cheat. Cheating How-To: Tips From A Mistress

Ready for it? People cheat because they're turning 30. Or 40, 50, 60 and we guess 70 or 80; but at that age (unless you're Hugh Hefner) who has the energy?

IllicitEncounters.co.uk, a hush-hush-find-an-affair, dating site in the UK says they notice an upswing in users right before a milestone birthday. Says a rep from the site:

The pattern is quite clear. Men and women approaching major age milestones - 40, 50, 60 - are seeking out affairs. There are various reasons for why this is happening. The prospect of getting older can be nerve-wracking for some. It can make us re-evaluate our lives and relationships, and ask ourselves whether we are truly happy. If we are unhappy at this point, we are likely to seek a solution - and it seems many married men and women see us as that solution.

Wow, we've been known to invent all sorts of red flags for cheating, but an age ending with a "9"? This is new. What next? Astrological signs, names that begin with "T"?

Hartley goes on to say an affair can make one feel "young and sexy" and help a self-esteem challenged person blow out their 40 birthday candles with zest. Thirty-nine, she says, is the most popular age on the site.

Whatever happened to a motorcycle? Or a membership to The Hair Club For Men? Highlights? A great vacation?

If all else fails, let's remember Jon Gosselin as our bad-case-scenario example. Wouldn't a nascent gambling addiction or embarrassing mid-life-crisis car purchase have been easier than all the hoopla?