Yes, that people will betray you, that people are greedy, that people value sex over all else, that people and the world are disgusting and depraved.
On the whole, I agree.
But that's no excuse for killing yourself. That's a recognition that God was right when He already said all that through his saints -- that this is a fallen world. What the depressed person needs is "the Great Physician" to save his or her life so that he or she can serve others and stop dwelling on his or her own pain. That doesn't rule out medical help with healing; but it puts the person's feet back on the ground and gives hope, and a way forward.