Empty Dinner Table
We see Norman left alone at the dinner table after Paul has left, followed by their mother to the kitchen and their father upstairs. It is a symbol that no one is talking about Paul's issues, instead walking away from them, leaving Norman to alone at the table symbolizing he is the only one who goes through it.
Booze
Paul gives a bottle of booze to Norman at the newspaper office to celebrate his return. Paul's liquor so close at hand is a symbol that he has something going on deep within him that he isn't revealing, but instead pushing down with alcohol.
Cutting Through
We see a train cutting through Montana which carries Norman back to his home. The train is a symbol of how innovation is being brought into this untouched land, and also, to some, it is a symbol of what is new cutting through what is beautiful and what has always been.
Shadow Casting
We watch Norman as he witnesses Paul shadow casting, which is a new fly fishing technique he's come to learn. Shadow casting is a symbol of Paul being an artist, a free spirit who is capable of great things.
Train Tracks
Jessie drives Norman through the train tunnel and over the gorge to get him home. This is a symbol of their relationship, how though it seems rocky and dangerous, if they do it together they have a chance of having something great.
