My feeling about it, besides heaping amounts of fear, is that I took a small, infant thing, raised it by hand, taught it to be itself, and am now setting it back on its own into the wide world. I'll miss the little sucker, but I take comfort in the knowledge that it is out in the world where it's supposed to be. Sure, I'll help it along where I can. Hover not-so-far away to make sure it doesn't founder, but, in reality, it has to stand on its own from here on out.
Good luck little book. Do your best!