Why did I do this to myself?

I’m writing. I am. But I’ve reached a major transition in the thing that is Cassiel and feel that I’ve worked myself into a pile of mush. This story is finished. I know where it’s going because I’ve already written it, but in rewriting, I have gone in totally different directions. My characters have changed. Oh, they’re still the same characters, but their voices have changed just as much as my writing has changed. It’s both exciting and disheartening to see my story taking such a turn. And now I’m trying to find the inspiration to just finish already. I want it done. Now. Ugh!!! I need a new project. I need to get away from this mess. I need to write.