If you were given one of the projects for your job, you'd complete it (and slog through the boring parts) because you wouldn't have a choice. Maybe a "project manager" (real person or virtual like a blog) to keep you accountable/on track would help. That won't stop the urges to chase "the next shiny", but will make resisting them a bit easier.

(I say this as someone with a hundred project folders, so I should follow my own advice. I will say when given a deadline to produce something, I deliver, warts and all.)