People should have emotional responses to real things. And I've often wondered why we don't treat depression with more realness. Trying to treat it with "positivism" is just more of the same thing that aggravates the depression: disconnection from real things. Positive attitudes are invariably supposed to be evoked for, once again, ideas.
Sunlight and exercise are two things that were mentioned as real things that can help re-connect people to physical reality (instead of ideas). Another important one is fundamental to human emotional and social health: affection. Simple physical touch from someone you trust and who will suspend judgement. Hugs. Hand holding. Sitting on the couch together. No expectations. No demands. Just freedom to be.
It seemed from the article/comics that some (maybe a lot) of the person's unhappiness was coming from the discomfort and pain of not living up to expectations imposed on them by others about their attitudes. Just being detached is not itself that horrible (and maybe it's less weird than being emotionally attached to imaginary things). But being made to feel/believe that you are a bad person, a defective person, a source of pain to others, that leads to a real kind of pain. Other peoples' facial expressions and tone of voice affects us on a much deeper level than conceptual imagination.
Like many mammals, some birds and other kinds of animals, humans are deeply wired to respond to the sounds and images of other humans expressing positive and negative responses to us. Those are the first place to go to work on immediate sensory treatment for depression. Because these social signals are so ancient, we can even get treatment from non-humans. Cats and dogs make people feel better. It's even been shown in studies that seniors in retirement homes feel better when they are given time with pets.
I'm not saying this is a guaranteed solution, but it hasn't been mentioned in this discussion, and it's very important. The way we socialize is inadequate to our biological needs.