Nihilitarianism

Depression is to keep trying what never works, usually, to force oneself to carry on. Studies find that the focus of depressed people is fixated as they get less easily distracted by stimuli outside of the point they're asked to focus their eyes on. This hyperfocus is similar to autism (and the opposite of schizophrenia) because both are caused primarily by glutamate, which modulates serotonin and dopamine. It should therefore not be treated with serotonergics but antiglutamatergics like memantine, which I can vouch for from my own experience.