Why all the sad songs (psalms)?

"My whole being is filled with distress; my life is at the very brink of hell. I am considered as one of those plummeting into the pit. I am like those who are beyond help, drifting among the dead lying in the grave, like dead bodies— those you don’t remember anymore, those who are cut off from your power. You placed me down in the deepest pit, in places dark and deep. Your anger smothers me; you subdue me with it, wave after wave.
Selah
You’ve made my friends distant. You’ve made me disgusting to them. I can’t escape. I’m trapped! "
Psalm 88:3-8 (CEB)

This is one of the most depressing portions of scripture. It's hopeless. There's no faith in it. But why are scriptures like this in The Book? Because the experience told by the writer is real and it's endorsed by God. What? Words like Psalm 88 are deeply comforting to the person on whom calamity has struck. If you hear your own voice in the words of Psalm 88, you are comforted to know that it is okay with God to feel hopeless and in despair, to feel like you are in a bottomless pit of pain.

The third chapters of Job and Lamentations are similar to this. If the "lights have gone out" in your life, these passages can be comforting in that you come to realize that God affirms and endorses your processing of your losses.

The Fire of Delayed Answers by Bob Sorge is my reference and inspiration for this post