In Chapters 13-19, Nomi decides that Tash’s drinking and staying out late are not as serious rebellions as “that library card of hers.” Why is getting a city library card a sign to Nomi that Tash has “gone too far” (120)?

Tash, Nomi's older sister, begins rebelling from the family. Nomi, a Mennonite girl, recounts the way in which Tash and Nomi's mother, Trudie, were excommunicated from the church. Tash, who has a significant impact on Nomi, uses her library card to bring home books "not by Billy Graham," as Nomi says (page 119). Instead, the books that Tash checks out of the library are "pamphlets about communism and Albania being a great place" (page 119). From her reading, Tash learns about the concept of a metaphor and "started applying it to almost every aspect of her life, and ours" (page 120).
Clearly, Tash's reading has made her question the life her family lives and their religious beliefs. Nomi feels that Tash has "gone too far" because Tash is moving beyond their world. Nomi says that Tash's embrace of communism and metaphors represents an even greater rebellion than everyday teenage rebellions such as drinking or staying out with boys because Tash's mindset has become more radical, and Tash has begun to reject the fundamental principles of their family's existence. Nomi even wonders if Tash has become possessed by the Devil, and Nomi begins biting herself out of confusion and pain.