I always just wanted to slap everybody involved with that ending.

But has Shane watched "Shane"?
Maybe that's what happened to the boy. Maybe he couldn't live up to the onscreen image and it just crushed him. Sent him down the wrong path. Twisted his thinking. Rumpled his feathers. Shook his world.
Made him question his basic assumptions about his place in the universe.
Shane, won't you tell us?...Shane?.........Shane?........SHANE?.......SHANE?????