Studies based upon ******* types have concluded that a significant part of the Western population couldn't have the ******* that figures in the public registers. Adultery has existed since humanity was created and probably it was even more common in traditional societies due the difference of age between both members of the marriage. The story of a young woman trapped into an arranged marriage with an older man, unable to satisfy her, is an archetype in all the ancient mythologies: Guinevere, Deirdre, Helen of Troy, etc. It is also well-known the instance of Candaules, King of Lydia, who enjoyed showing his wife naked to Gyges, one of his ministers.
I think in modern times cuckoldry is just adopting a socially acceptable form. As Western societies are becoming more multi-racial, the chances of having a black lover are higher. And in that sexual competition black males are superior, or a number of cultural and biological factors converge to make the sex between a white woman and a black male much more intense.