I remember reading the passage below when I was suffering from depression and thinking how perfectly it described how I felt in the darkest moment of my life. There are terrors you can’t see.

I didn’t understand depression until I had it. I had to come face to face with that unseen terror. And it’s hard to describe with words. How effectively terrifying it is. It forms and molds your own thoughts into weapons meant to destroy you. Just as your body can produce antibodies to kill you physically your brain can produce thoughts to destroy you emotionally.

David Foster Wallace fought major depressive disorder for more than 20 years before taking his own life. He understood the battle. He tried for years to live only to end up trapped by that other terror.

“The so-called ‘psychotically depressed’ person who tries to kill herself doesn’t do so out of quote ‘hopelessness’ or any abstract conviction that life’s assets and debits do not square. And surely not because death seems suddenly appealing. The person in whom Its invisible agony reaches a certain unendurable level will kill herself the same way a trapped person will eventually jump from the window of a burning high-rise. Make no mistake about people who leap from burning windows. Their terror of falling from a great height is still just as great as it would be for you or me standing speculatively at the same window just checking out the view; i.e. the fear of falling remains a constant. The variable here is the other terror, the fire’s flames: when the flames get close enough, falling to death becomes the slightly less terrible of two terrors. It’s not desiring the fall; it’s terror of the flames. And yet nobody down on the sidewalk, looking up and yelling ‘Don’t!’ and ‘Hang on!’, can understand the jump. Not really. You’d have to have personally been trapped and felt flames to really understand a terror way beyond falling.”
― David Foster Wallace