Complex sentence: The boys make up and go to one last picture show together then after Duane leaves on the Trailways bus to Korea, Sonny gets back with Ruth who was upset by Sonny's abandonment, but glad to see him nonetheless.
Split into simpler sentences: The boys make up and go to one last picture show together. Then, after Duane leaves on the Trailways bus to Korea, Sonny returns to Ruth who, though upset by Sonny's abandonment, is glad to see him nonetheless.