I think there is a difference between having something like depression or anxiety due to circumstances and having it even tough everything else is fine. I also think there are some issues that do not come from the environment, at least not directly (personality disorders, or schizophrenia for example.) Of course these can also be influenced by the circumstances, but often times the issues will happen regardless of the exact situation. And treatment should be tailored after the issue, medication can sometimes help and sometimes should not be given.