"Praise the Lord O my soul and FORGET NOT ALL HIS BENEFITS"
Hmmm. You are assuming that said "soujourn" into insanity leaves one with the ability to perceive the contrast when sanity returns. I KNOW it's not that simple. There's no "on" and "off" switch for sanity/insanity.
Insanity, I think, has to be the very worst of human ailments. One's SOUL is affected. We can only pray for those poor people and leave them to God's enduring love and mercy.