You know how on the old cartoons, when a cartoon character runs off a cliff, he doesn't fall - he just keeps running? And he is perfectly fine, until he looks down and realizes there is nothing whatsoever holding him up? And then he plummets all the way to the ground, yelling, "Aaaiiieeee!"
That, my friends, is a perfect parable for parenting. There you are, running along on air for 12 or 13 years, thinking that, so long as you raise those kids "right," you are in control. And then, after all that time of living with this nice cozy illusion, your newly-minted teen makes you, figuratively speaking, look down. And you realize that you've been living a lie and there are no guarantees. Not their safety, not your sanity, nothing is really under your control (except maybe the car keys, but you have to hide those really well).
So, it's been 2 years since my Anna turned 13, and I just have one question: at what point do I get to stop yelling, "Aaaiiieeee!"?