One of the more useful books I've read on the topic of mental illness is Adventures in Psychiatry by Dr. Abram Hoffer, a research scientist and medical doctor. He did the first double-blind studies of using vitamins to treat schizophrenia in the 1950s. He gave LSD to an architect to help the architect understand what patients may experience, so as to make the design of a clinic better. Those are just two examples of interesting things he did in his life.

The book can be hard to find on Amazon, or in brick-and-mortar book stores, but it can be ordered from the International Schizophrenia Foundation http://www.isfmentalhealth.org/resources/booksfilm/

The ISF also has resources on other types of mental illness from an orthomolecular medicine perspective. I realize that the orthomolecular approach is controversial, but I think that it helps at least some of the people who experience mental health problems, and I think it is not just a placebo. That said, I don't think it has a complete picture of what the problems are and how to fix them. No one in the world has that yet, that I am aware of.

I'm not sure if this falls within the type of discussion you want to start, but I thought I'd give the book recommendation, and point out that there is another option for people with mental illness to look into besides talk therapy and prescription drugs.