You become yourself with another self: you make a pair, and in doing so you see the future in each other's eyes.
Indeed recognizing that with death the relationship must end gives marriage much of its human pathos. The vows say 'I'll love you for as long as I possibly can. I can't love you after I'm dead, because I'll be dead.' Marriage begins from death, as it were, and work backward to fill the intervening period with love.
You know, I like Dubstep-ish Bass Drops as much as the next guy, but it's odd it's the only way to tell current from 10-15 yr old things.