He had a documented history of depression. By definition, he was not in sound mind, there is ample precedent of people suffering from depression, trying and failing to commit suicide, and later recovering and thanking those around them for saving them.

This idea that "one's mind is sovereign over their destiny" is unsustainable in practice. There are many versions of it floating around, for example related to gun control issues. You just can't create policies that ignore the reality that a large portion of people are not rational a large fraction of time.