I think the main reason that many see mental illnes as the fault of the person is because the symptoms involve the persons behavior.
Also medicine for the longest time believed all was the fault or weakness of the indivigual.
It is only in the last few decades that medicine is able and willing to see the brain as a funtioning organ that may not be working as it should.
One of the best examples of the acceptance and change in the former view is that insurance and medicine is not separating mental illness from any other illness.
In the state where I live legislation has been passed that over the next three years all mental illness claims must be paid out the same as all other illness.
This is a milestone in recognition of illness rather than fault.
I find it sad that some still cannot see this as well.
God did not promise us a perfect world, he does promise us he healing and perfect spirit to be content in all things.
All is of God Our Father, all is to his Glory.
God bless, pickles