Sex either enables or disables the compatible merging of the male and female natures into a successful relationship. Not coitus but the before and after expectations. Sex differences make the difference.
COMPETITION—The Male Strength
Men are made to compete with men. (Disregard table and fun games here.)
Except when trying to conquer her, a man avoids hard-headed competition with a woman. Women too easily outtalk or outsmart men seeking to conquer them. So, men conclude, it’s best to avoid competition on other matters. The prospects of conquest warrant head-to-head mind games, but nothing else.
Men don’t want a woman to think he can’t hack whatever comes up, so losing mind battles reveals incapacity. It can too easily demo some bit of insignificance, which he fears.
Pushy male dominance is a surefire way to avoid competing with her, so he uses it to stop discussion, squash dissent, and avoid loss of face. It’s his nature, not the woman. (Male subordinates of female bosses often favor indifference rather than compete to win a point or advise her.)
After conquest, he expects sex to be cooperative and not competitive. Why not? Her nature favors the former over the latter. But that’s not the whole story.
COOPERATION—The Female Strength
Men do whatever women require in order for men to have frequent and convenient access to sex. When Womanhood speaks, men pay attention. If a woman sets standards and high expectations, a man will step up, elevate his effort, and smooth his attitude—but only before conquest.
Beyond that turning point, he expects routine access to sex with her; it was the target of his natural conquering spirit. Conqueror’s rights are an intrinsic primal urge, hardwired and hormonal. Consequently, he can’t stop his expectations; she certainly can but at risk of losing him.
A man will not long play games or otherwise compete for sex with a woman he has conquered. If she persistently uses sex to get her way, he will rebel quietly, privately, noisily, or physically. Whichever way he chooses, he won’t tolerate it very long and soon seeks another woman.
It’s especially true in marriage. He paid the ultimate price to have frequent and convenient access. When she starts to pull back or shy away, his competitive spirit energizes him, because she challenges his conqueror’s right. So, he pushes for and expects easier access or unlimited sex to prove that he’s right. This makes her resent, resist, rebel, and retaliate in order to restore her self-respect. He pushes harder, she does too, and they start living separate lives under the same roof, or worse.
Compatibility has one switch for sex. They compete before conquest. They cooperate after.

