People who have been pushed to a mentally dangerous place seek one thing = peace of mind = nothing else is particularly important.

People who have been pushed to a mentally dangerous place = the value of things has fundamentally changed = the world's colors change = they can distinguish between what is a lie and what is essential = they understand what is necessary and unnecessary for themselves.

They think of sadness as a friend they will be with for a long time in the future = they see a small sparkle in the pale-colored scenery = the world's colors change = their previous values change = things they thought were good become not so good, and things they thought were bad become good.