End of an Era

My mammoth book collection/accretion is getting a first hacking-down today. Roughly 12 paper-boxes of books and 10 smaller boxes of comics are going to the Salvation Army this afternoon, to be followed next month by many more.
I'm a little depressed. I know it needs to be done, and that the things I'm donating are largely things I (probably) would never read again, but there's always misgivings in changing things that you feel define you. For me, having lots and lots of books defined me; I'm a book guy. I always was a book guy. Back in fourth grade, I had one shelf on a bookcase where I put my earliest purchases-- and told my mom that that was the start of my collection.
That collection now fills a dozen bookcases and nearly 50 boxes.
But Kat and I are having a baby and the two cannot coexist. She needs a room of her own; my books... do not.
So I recognize the necessity and look forward to the reason for making this change, but excuse me if I'm not wildly celebrating getting rid of stuff I spent almost 40 years accumulating.
[/self-pity]