What does Bridget give up in her quest to be the "cool girl" in the novel, You Go First?

At the beginning of the novel, it is clear that Bridget and Charlotte’s friendship is falling apart. Bridget gets all new clothes and is shocked when Charlotte does not get anything. Bridget insults Charlotte for her intelligence and calls her a parasite to her other friends. In her desperation to be the cool girl, she breaks the closest friendship she has likely ever had and throws away everything she once cared about.