"While the 70s were not a terribly innocent time by 1950s standards, they were NOT very similar to today. Most of the girls I knew who were sexually active tended to do it with a boyfriend who they were dating."
What I'm hearing about today is "serial monogamy." People will hook up for a while, have sex -- even get married. Then they move on to someone else.
Shows how much the very concept of "relationships" has been devalued.
Well yeah, but that is not necessarily a bad thing. In the past, women were dependent on the man they married. If he ended up being a bad guy, the woman was screwed.
Now, women are able to make it on their own and they enter relationship for emotional reasons rather than just financial ones.