Yes - there is a fundamental difference between the sexes when it comes to the issue of visual stimulation. In general, men are extremely visually based in their sexuality - thus, the proliferation of pornography, advertising, and media that is geared toward men. Women, are more swayed by the concept of caring and being protected (i.e. loved). That said, the majority of women's product placement (cosmetics, clothing, etc) is geared toward making a woman more appealing to the opposite gender (i.e. "sexy").
Of course, these are all stereotypes.
There are some women who are very turned on by pornography and some men who are disgusted by it. It really depends on the individual person and their likes and dislikes.
At it's healthiest, sexuality and love should be linked in a relationship. Sex is a deep and meaningful way of expressing love toward a partner. Therefore, I do not believe they should be separate, as you mentioned. However, I agree that there is a disconnect between sex and love in popular culture and, often, incorporated into a man's way of thinking. Many men believe that viewing pornography and looking at other women is healthy and normal and should have no effect on their relationship. In turn, many women feel hurt and betrayed. The best that we can do as psychologists treating individual couples is to help that couple come to an understanding about what is (and what is not) acceptable to the other partner. While it would be ideal to change the culture as a whole, it is probably a bit unrealistic.
Does this answer your question?