Sex is more than just a biological need for men.
It goes without question that men and women are different. And the topic of sex is no exception. I think, at times, this is a good thing. If men and women were equal in this area, we would have either a lot more people around (because everyone would be getting busy!) or we would have a lot fewer people ... because everyone would be having less sex.
The fact is that, typically, one gender pursues it and the other gender controls the frequency. How often we think about it, how often we want it and what it means to you differs between genders. Much of this is tied up in how we're wired and the ins and outs of our brain chemistry. So let's talk brain chemistry, and neurotransmitters. Both men and women have the same neurotransmitters, but they don't necessarily send the same messages at the same time.
An important neurotransmitter that is released during sex is oxytocin, dubbed the "cuddle hormone". There's also vasopressin, which is responsible for bonding. Although both men and women release these hormones, they do so in unequal amounts. In women, for example, estrogen increases the effect of oxytocin in their brains.
The release of this cuddle hormone helps explains why women are generally the caretakers. Alternately, in men, testosterone increases the effect of vasopressin — which results in feeling attached and protective. Interestingly, men only release oxytocin with women they love. Another important fact? The effect of oxytocin dissipates in men right after orgasm. So, if a man wants that feeling again he needs to have sex again. Hmmm, maybe that's why men want more sex.
This brief return to science class helps explain one of the most important things that happens in relationships: attachment. Attachment is the drive to feel connected, wanted, important, valued and desired by a significant other. As you can probably guess, men and women differ here too. Not in the need for it, but how we get it. In my practice with couples, these discrepancies are very apparent. One way women get a feeling of closeness, an essential component of attachment, is through talking and the sharing of feelings. Women are far more likely to talk about how they feel than are men. Our western culture supports and encourages women to express themselves and their feelings from the time they were little girls. Through this sharing of deeper emotions, women develop close bonds with others. So it's no suprise that women needs to feel attached first to be in the mood for sex.
In my experience with couples, for women, sex goes to the wayside when they feel emotionally distant from their partner. Men, on the other hand, are not supported or encouraged to express their emotions. To do so comes with the risk of being seen as "girly" or overly feminine. This inability to express one's emotions has seriously cut men off from how they actually feel. This is one of the biggest problems I see in relationship compatibility.
This leads us to the important points. One: In order for men to feel the effects that women get from oxytocin, they pursue more sex and want it from the women they love. Two: The fact that the woman is willing to have sex with him helps him fell connected, wanted, important and valued ... which is exactly what he needs for attachment. This helps him feel that he has made his woman happy and he's doing a good job. Win-win!
Sex, then, allows men to experience all the effects of those neurotransmitters that women get from just talking about and sharing their feelings. Despite what you may believe, for men, the need for sex is more than just the orgasm. It means that he's wanted, needed, important, valued and desired. Sex is more than just a physical act. It helps fulfilling the primordial need to be attached to a significant other. Think of it this way, "You like me enough to have sex with me and that's how I know you think I'm pretty."