"So, why is ennui unusual and crippling? Most people are manipulated by little bursts of pleasure and displeasure in response to stimuli once the brain abstracts them. Your whole life is a little symphony of up and down votes coming from pre-sentient parts of your brain, pushing you to move in certain ways. That’s all that willpower and character really are, initially.
Depression mutes the upvotes. You don’t get strongly rewarded for doing anything. This is why it suddenly seems like socializing is hard, as there’s no burst of reward chemicals to make the stress of trying to model another primate pleasant. This is why cleaning is hard, since all you can feel is the effort and none of the reward for “doing the right thing”.
Eventually, the rest of your brain mutes the downvotes. There’s nothing to compare them to, so they’re ignored. Then you’re numb, and not really operating that well since you’re built around the idea of perceiving inherent rewards and punishments for certain activities and you have nothing to guide your actions. Life is pointless and confusing.”