A few thoughts. First of all, there’s been a huge disparity in female sexual satisfaction (as narrowly defined per your article, videlicet: achieving orgasm) between the USA and Western Europe. Even 30 years ago surveys were showing that around 30% of sexually active US women usually or always reached orgasm during sex while 70% did so rarely or never; meanwhile in Europe the statistics were precisely reversed. So clearly the deeply fearful sex-negative US culture is hurting everyone.

Secondly, the adage “familiarity breeds contempt” can be modified to state more accurately, “familiarity breeds boredom.” As we’re a partially monogamous species both physiologically and psychologically many people choose to have clandestine affairs as a way out of matrimonial bed death; unfortunately the lies required end up corroding the relationship. Swingers do better in this regard by intentionally generating a sense of “otherness” in their partner by means of sexual intimacy with others, but emotional insecurities common to most people make this a very problematic solution for the population as a whole.

Personally I doubt there is any one solution to the dilemma our species faces, but if we at least understand the problems inherent in a long-term relationship then perhaps some of the guilt and disappointment and resentment that so many couples end up with could be to some degree avoided or minimized.