Author's Note:
This story (which was my first foray into fanfic) grew unexpectedly long, and when I thought it was nearly complete, I received some advice that caused me to do some fairly significant restructuring in the second half. So if you have been reading it all along, I strongly suggest that you might want to reread, if not from the beginning, at least from chapter 9; the changes prior to that chapter are relatively small.
Thanks especially to Watson at TOR.n for her suggestions; the improvements in the structure can be credited to her. Any remaining infelicities remain solely my responsibility; it's an imperfect world, it's an imperfect story. That's okay. And thanks to everyone who has read and commented on this – I've appreciated all the encouragement.