Bear blames Joel, the victim of his and his friends’ bullying, for their well-deserved punishment, which shows that Bear isn’t self-reflective enough to recognize that they’re responsible for the consequences of their own actions. Chase, by contrast, has come to recognize that he and his friends are—as the saying goes—lying in the bed they made. Aaron’s attempt to make peace between Bear and Chase demonstrates his continued loyalty to both his best friends. When Chase keeps snapping at Bear, Bear snaps back that active, sadistic enjoyment of Joel’s psychological suffering (not mere callousness) motivated Chase’s bullying of Joel. Bear may or may not be right—it’s not clear how insightful he is—but Chase, already disturbed by his own past behavior, is more than ready to believe his condemnation.