"Women’s anxiety in relationships tended to decrease over time when their partner showed high levels of sexual desire. Basically, the female participants felt more secure in their relationship if their partner wanted to have sex with them a lot. The authors believe this is because women consider men to be innately sexual creatures, so they derive relationship validation from sex. The authors explain:
Accordingly, a woman may perceive her partner’s sexual interest as a sign for his willingness to invest resources in the relationship (e.g., love and intimacy; and his lack of sexual interest as a sign of disinterest in the relationship.
However, the opposite occurred for men. Men’s anxiety decreased over time when women showed high levels of emotional intimacy, but low levels of sexual desire. The more sexually aggressive a woman was, the more her partner remained anxious in the relationship. The authors write:
Men’s anxiety decreased more sharply over time when their partners displayed less sexual desire."