I get stuck when I write. I struggle. So I've started asking myself basic questions about my story, and then I read up on what I'm "supposed" to be doing and weight it against what I am doing. So here's a question I asked myself about a short story I'm writing right now, and the solution I found:
What is the setting of what you are writing?
I always seem to start huge. Like Star Wars, or Lord of the Rings. I try to create entire universes, and then I get frustrated that the story is broken, and disconnected. Then I listened to Robert Mckee. He explained that the world can be massive, as long as the setting of the story is not. The antagonist can be an entire army or world, as long as the setting is the van, the bunker and the living room where the characters unfold.
But that seems like a creative limitation! Yes, and we thrive on them!
McKee says that the setting must be so small, that the writer can know it to the depth that God knows this world. Only then can an artist make a real story.
I'd listen to him, he's a doctor...not really but they call him the "Story Doctor" so...