@toosober That's okay! I totally thought the same thing, oh God... my published book is a collection of short stories I did because I was pretty desperate to work on something shorter. Personally NaNoWriMo can help with long-project fatigue; if I only work on it once a year, and then at high speed, then it's okay...
So it's totally not something out of reach for you. If you don't want to write long-term, that's okay, and sometimes you do find that what you were thinking of works better as a short story (I had a novel idea I couldn't figure out how to write until I cut it into a short story, and then it flowed naturally.) Don't be afraid to experiment! I also like using beat sheets (google "save the cat beat sheet" for my favorite) to write; they help a lot with organization. Oftentimes I'll think "hm, something is missing," and when I chart it out Save The Cat-style, I realize I was missing the Dark Night of The Soul or something. Laying out your scenes against a template can help a lot!
I'm glad I could help ^_^ my message box is open anytime!