As writing has become something at which I want to try to make a more serious effort, I've spent more time reading writers who write about writing. One of the things that has stuck with me from the things I've read that is proving to be true in trying to finish this project is that it's tough to cross the finish line and have the project be completely done. It's easier to move on to what I want the next project to be, or to find something (anything) else to occupy my attention than it is to put the finishing touches on this and have it available for anyone in the galaxy to see.
I'm glad I made the decision a few months ago to say on this blog that I'm writing the book and to give myself a public deadline for getting it finished. I probably won't quite meet that deadline, but I'll be within a few days of it, so it served its purpose of keeping things moving.
So I think I can... I think I can... get this finished. It's not that it's all that difficult to do- the most challenging part of writing it has already been behind me for a long time. The hard part, as those other authors attested, seems to be crossing that line from "I'd like to write a book," or "I'm trying to write a book," to "Here's a copy of it."