1st time: started dating at 19 (both of us) and then married while still 19 about 6 months later. Surprisingly this didn't work out very well. How odd. Divorced about 5 years later.
2nd time: I was 24, she was 20. Dated momentarily. Maybe 2 months and then she moved in. By some strange miracle, it's 6.5 years later and I can hear her voice in the next room talking to a co-worker (she doesn't work here, but dropped me off at work and hasn't left yet). We got married about 4 years ago.
It's not the way I planned it, that's for sure.
Oh, on a side note, I met my wife (the current one) when I was about 15 and she was about 11.