Stained Red by My Perfect Compliance

From the back cover

Three years in a facility have taught Ashton to obey. When his older sister Camille brings him home, she orders him not to wear his corpse-like expression; he answers by drawing a shard of glass across his own face. His adopted brother Noah threatens him, then beats his own arm with a baseball bat, and his fiancée Jocelyn demands an apology. Ashton vaults from a third-floor balcony instead.

He survives, but the voices in his head insist that only absolute obedience, followed by death, can return him to his original world. His family argues over him: Camille calls his injuries a performance, Noah plays the wounded victim, and Jocelyn admits her heart stays with Noah. Cornered, Ashton takes a fruit knife to his own neck.

Security footage finally shows Noah striking himself, yet Camille blames Ashton for Noah's asthma attack and urges another sanity test. Jocelyn stands over his bed, asking whether his new docility is only a trick.