Stephanie Perkins said this quote

St. Clair gets a crush on Anna. He's torn between her and Ellie, and he spends so much time running between them that he hardly has time left for Josh. And the more time that Josh spends alone, the more he realizes how alone he actually is. All of his friends will be gone the next year. Josh grows increasingly antagonistic toward school, which makes Rashmi increasingly antagonistic toward him, which makes him increasingly antagonistic toward her. And she's upset because Elie dropped her as a friend, and Meredith is upset because now St. Clair likes two girls who aren't her, and Anna is upset because St. Clair is leading her on, and then St. Clair's mom gets cancer. It's a freaking soap opera.