Looking for that happy ending? Try plotting your story using the Hero's Journey. Our own Caris Roane swears it helped her.
I found three videos on YouTube I found helpful in explaining this pattern of narrative identified by Joseph Campbell.
The Hero's Journey, explained with examples from The Matrix, Star Wars, Harry Potter, and the Lord of the Rings - 10 steps
In 5 steps with examples from The Wizard of Oz, Harry Potter, and Star Wars
The Journey shown with examples of Disney movies.