Identical

Ellen Hopkins' Identical is a verse novel which tells the stories of identical twins Kaeleigh and Raeanne Gardella, the 16-year-old daughters of a district court judge, and a candidate for the United States' House of Representatives. While their mother campaigns for the House position, Kaeleigh and Raeanne are left in the care of their alcoholic father and have to deal with maintaining the family's "perfect" appearance while struggling with the secrets that tore them apart.

Tropes used in Identical include:

Abusive Parents: Mr. Gardella is sexually abusing Kaeleigh, and Mrs. Gardella is far more focused on her career than her family.
Alpha Bitch: Madison.
Always Identical Twins
Angsty Surviving Twin
Freudian Excuse: Mr. Gardella's "reason" for his alcoholism and other issues in the book.
Parental Incest
Self-Harm: Kaeleigh is a cutter and a binge eater, while Raeanne suffers from bulimia.
Split Personality: The end of the novel reveals that Raeanne died in a car accident several years earlier, and that the subsequent sexual abuse visited on Kaeleigh by her father caused her to develop Raeanne as a separate personality in order to live out her repressed sexual desires.
Split Personality Merge: When the truth about Raeanne's death comes out.
Twin Switch: Raeanne passes herself off as Kaeleigh a couple of times.