 McCullough writes that chronic depression (i.e., depressive disorder in adults that lasts continuously for two or more years; one year continuously in adolescents), particularly the type beginning during adolescence (early-onset), is essentially a refractory "mood disorder" arising from traumatic experiences or interpersonal psychological insults delivered by the patient's significant others (nuclear or extended family).The chronic depression mood disorder, at the core, is fueled by a generalized fear of others resulting in a lifetime history of interpersonal avoidance.The disorder rarely remits without proper treatment.