How does the author use symbolism in the nonfiction book, This Is Going to Hurt?

The apartment that Kay fails to get with H is important because it signals the end of their relationship. As the novel progresses, Kay's relationship with H begins to struggle under the difficulties of Kay's job. When they fail to secure the flat, Kay notes that tensions were "running high at home" and that his relationship was "slightly fraying at the edges" (103). The unsuccessful apartment becomes an important symbol for Kay's ultimately unsuccessful relationship.