SOMETIMES THERE JUST AREN’T ENOUGH ROCKS
The still image from the scene above is based on the painting below called Christina’s World by Andrew Wyeth. Christina was Wyeth’s neighbor who was crippled by polio. The haunting and mysterious quality of that obsessive painting is amplified by that additional information.
The directorial choice to so directly reference that painting in this scene serves to emphasize how emotionally crippled Jenny still is at this point in the movie.
Christina’s World by Andrew Wyeth, 1948
Like Christina, Jenny can see her home, but she is not emotionally able to make that journey. So she runs away again which also sets Forrest on his run and coincidentally on to another Wyeth reference, the Marshall Point Lighthouse.