Content Warning: This section of the guide discusses toxic relationships, mental health conditions, sexual abuse, and psychological abuse.

Bye, Baby explores the complex psychological dynamics that can pervade human connections. Depicting the relationship between the protagonists from both perspectives, Lovering illustrates how friendships can change as individuals age and evolve. In the case of Billie and Cassie, a seemingly inseparable childhood bond translates to a toxic dynamic in adulthood.

The novel’s backstory establishes that the protagonists’ childhood friendship has its roots in trauma and shared secrets. Their bond is strengthened by Cassie’s support of Billie through her mother’s illness and the sexual abuse inflicted by her stepfather. Cassie’s role in Wade’s death cements their intimacy with a secret they can never share with anyone else. In these sections of the narrative, Lovering captures the intense nature of childhood friendships. Billie and Cassie’s rapport evokes the fervency of a love affair, as they vow to always be there for one another and express the exclusivity of their bond by using the affectionate nickname “Baby.”

By the time they reach adulthood, the protagonists’ differing values and lifestyles make them unlikely friends. Nevertheless, Billy remains intensely loyal to Cassie, still considering her to be her best friend.