The mental health system is broken because psychiatry was captured by the pharmaceutical industry in the 1980's. Robert Whitaker's book Anatomy of an Epidemic [1] examines how commonly-used drug treatments actually worsen patients' mental health, and chronicles the capture of the American Psychiatric Association.

[1] http://robertwhitaker.org/robertwhitaker.org/Anatomy%20of%20...

In spite of everything, science is making a little bit of progress in understanding why people have various mental conditions. For the most part, patients are 'exhausted', because of poor metabolism, malnourishment, etc. Inflammation is a huge factor, as is cortisol deficiency.

I've posted some links before - see my comment history.