Complex sentence: However, she is still paranoid about the hitch-hiker, and when she sees him on the road and tries to run him over, the sailor, who can't see him, begins to fear for her sanity and leaves her.
Split into simpler sentences: However, she is still paranoid about the hitch-hiker, and when she sees him on the road and tries to run him over. The sailor, who can't see him, begins to fear for her sanity and leaves her.