Psalm 88

"The saddest psalm in the book"  because it is a lament, without the usual elements of trust and praise.  This is mentioned by both study bibles.
 
Of Heman, a leader in the guild of the sons of Korah, per NKJV notes.
    See IKings 29:31.

"Oh Lord God of my salvation....." begins the song.  The writer knows Who to turn to and does so in spite of his feelings.  Indeed his (very intense) feelings do not sway him from running to God.

He pleads with God to hear him, and launches into a lament about how he feels...like death. 
His soul is troubled, he has no strength.  Even others perceive him as a dead man.
He feels utterly abandoned and cut off, isolated and alone.....with no way out.

He does attribute his state to God's hand, recognizing His sovereignty.....without anger, it seems. But as is customary in most other Psalms, there is no confession or assertion of his innocence.

He is in utter despair.  He cries to God continually.  "Lord, why?!"  He continues to ask questions of God, trying reason with him it seems.  If like the dead, can I praise You?  Neither can others praise you regarding my state!  How does my state of affliction demonstrate Your lovingkindness, wonders, praise, righteousness?   I have called upon You, and You only, but it seems You have turned away from me!  I have suffered since my youth! and am distraught due to Your wrath!.

Loved ones and friends alike are far, far away.
~~~~~~~~~~~~~~~~~~~~~~~~~`

I found several positive notes in this sad, sad, lament.
First, he does know Who to turn to.  As said, his suffering does not cause him to sway....he               recognizes God as his only source of help.
Secondly, he recognizes God's sovereignty, even when it has a negative impact on him.
Third, he is persistent,  calling upon God continually.  This speaks to me of a trust, even though not     voiced specifically
Fourth, he is concerned not only for himself, but for God's Name. He wants to be able to praise          Him himself, and not only that, but for others to do so because of what God has done.


I wondered, and study notes also, if perhaps he was a leper, thus the references to be shut out, and isolated.

Last:  I love what the NKJV note said :  "the 'why' of human suffering is rarely easily answered, especially to the sufferer's satisfaction."

No answers are indicated in the psalm.  But he knows God is his God, that He is sovereign,  He is able, and He is right.

Oh that I might follow this example when I am in the depths of a fiery trial!