In 2004 the journal Science reported 900 women when polled gave "intimate relations" a positive score of 5.10, compared to 4.59 for socialising. Housework scored 3.73, which was better at least than working at 3.62.
It's also been reported often in the past few years that being married makes you healthier and happier, in part due to sex. About 40% of married people have sex twice a week, compared to 20-25% of single and cohabitating men and women. Over 40% of married women said their sex life was emotionally and physically satisfying, compared to about 30% of single women. For men, it's 50% of married men are physically and emotionally contents versus 38% of cohabitating men.
This creates the rise in products to enhance that "experience" with a selection of prescription drugs and non-prescription products like extenze. Which then creates the old adage - Make love not war...