This story was ripped off by the Twilight Zone. It was an almost identical story of a girl who took off from the East Coast to drive across country. She had died in a wreck at the beginning of her trip, but she didn’t know she had died. She kept seeing the same man by the side of the road everywhere she went. Same story. I know he’s dead and doesn’t know it.
The main character doesn't know who he is?
I don't know about that one...