Jessica Valenti's great book The Purity Myth: How America's Obsession with Virginity Is Hurting Young Women (Seal Press, 2009) offers the following beautiful solution to the perennial problem of what should "count" as sex:
It isn't sex unless you've had an orgasm. That's a pleasure-based, non-heteronormative way of marking intimacy if I've ever heard one. Of course, this way of defining sex isn't likely to be very popular among the straight-male sect, given that some would probably end up not counting for many of their partners. (21)
I have been present at way too many discussions of what should or should not be considered sex, and this definition seems perfect. I need to go and rethink some aspects of my life now that I have accepted Valenti's definition of sex.