Hey dude, I hope my post on the Ex Zodiac page wasn't upsetting at all, I can be a bit blunt sometimes!
I totally understand where you're coming from now. As a programmer staying focused on a single project has always been a problem, and I think that a big part of the reason game jams have caught on is -- making something within a timeframe that can keep your attention.
A full sized project is a lot of work and even though a lot of problems as "solved" by engines for you (you don't have to blip polygons to the screen by hand,) they're replaced by new problems in the form of complexity.
If you think releasing a public demo would help your motivation then I say you should go for it, but you really need to be introspective on what is holding your motivation back. Perhaps some feedback could be cathartic, but maybe you are just burned out on the project.