The Psalms powerfully express the widest range of the spectrum of emotions in human experience: from despair to hope, from complaint to praise, from death to life, from excruciating depression to overwhelming joy, from defeat to victory. The extremes are often related to which is closer, God or the Enemy: the closer God is the more peace and joy; the closer the Enemy the more sorrow and turmoil.
Psalm 88 may be describing the lowest depths of despair, darkness, depression, and discouragement because Death is the enemy most near. God and life are far away; only complaint and no praise and everything is negative. The only positive note is that he is still praying to the God of his salvation.
It is instructive to note the close connection between Praise and Life and between Complaint and Death. In the Revealed Word heaven is always pictured as only praise and no complaint; hell is always pictured as no praise but only complaint. It would seem that the sanctified, Spirit-filled believer can move closer to God and life and heaven on earth by turning complaints into prayers and praises. So we read this Psalm in the context of the entire Psalter.