So far, there seem to be three broad social narratives that contribute to the topic (premarital sex in case you've forgotten).
- Since the end of WW2 or so, the ideal marital relationship has been based on romantic and intimate love. The concept of a "soul mate" gets introduced and (probably) greatly affects peoples' decision in a marriage partner.
- Going back a little further, we've seen an increasing "deregulation" in sex. This (probably) started with first wave feminism, proceeded to homosexuality, and now gets turned onto premarital sex. Slippery slope arguments abound and often with good reason.
- Marketing geniuses have found out how easy it is to sell a mundane product by using sex. This commodification of sex has transferred sex from something relational (something that happens between two people) to a product to be consumed (relationship has no part in the equation--solely orgasm [or at least the hope for one]).