Sexual drive varies from person to person.
I have seen countless hubs and blogs written by women trying to figure out how to put the "spark" back into their marriages.
In fact the majority of "self-help" books concerning relationships, sex, passion, and romance are purchased by women not men.
Having said that I do believe their is a difference in a man's mindset regarding sex when he is single or free to date around compared to when he is in a monogamus relationship or has taken the vow to "forsake all others".
His sex drive may be the same but when he's dating more than one woman the women involved may not feel pressured or obligated because he has "other options". If one woman rejects him for whatever reason he can call on another woman to see if she is in the mood.
However if this same man is (attached to one woman). He did so believing that SHE would be the ONE to address his physical and emotional needs whenever possible. When this woman rejects him the potential for feeling hurt is more likely. If the woman he "forsake all others for" doesn't desire him then he is either not going to "feel loved" or may believe he made a mistake.
A woman who cooks, cleans, purchases groceries, and does laundry may see all of these things as an expression of her love.
However those are all things he could do for himself or things his (mother) did for him.
"Sexual intimacy differentiates maternal love from romantic love".
Awhile back I wrote a hub titled "Sex And The Married Man"