I think that once-common scenario is very rare these days. And when it does happen, you usually see the protagonists on Jerry Springer a couple of years later. ;)
I'm one of the high school age romance survivors (he was 17 and I was 16), 'course we've been married 25 years with NO kids and it WAS a long time ago. (They should add/subtract kids to/from the equation.) I've also been blessed with a great guy.
I know quite a few. Of course most of them waited until college or later to marry - I don't know hardly any that got married directly out of high school...