Society has always had a deep-seated fear of mental illness. Even today in 2009, when more is known about mental health than at any time in history, there is still a stigma attatched to depression and similar debilitating conditions.
Even though we know such conditions are not infectious, there is a sub-concious avoidance of the condition, and the sufferer - I know, I havd a complete breakdwon twenty years ago and was hospitalised for three months and off work for a year. My immediate family were wonderful, but my in-laws, a different generation - preferred to liken it to a bad does of flu, not somthing I live with on a daily basis.
In less enlightened times, it was the norm to isolate such individuals, where they couldn't frighten the horses! No we have swung too far the other way with a laughable concept called 'care in the community' which is a great excuse to demolish hospitals and build on the land., and leave sufferers to get on with it, surrounded by the aofrementioned society who fears and shuns them.
Our society hates and fears its ill members - that has a few more generations yet before any real change will come.