Life has its seasons. In nature there has been a continuous cycle of seedtime and harvest, cold and hot, winter and summer (Genesis 8:22) since the completion of the flood.
Life has its peaks and valleys. There is a time to weep and a time to laugh, a time to mourn and a time to dance (Ecclesiastes 3:4, cf. vv. 1-8).
The book of Psalms clearly recognizes the spectrum of human emotions that comes with being made in the image of God. Numerous psalms were written while their composers were desperately clinging to the final thread of their frazzled faiths. David cried out to God from the dark, dank pit called depression (Psalms 42, 43); he beseeched Jehovah while in a cave of overwhelming fear and a front row view of the valley of the shadow of death (Psalms 3, 57); he personally knew the overwhelming, agonizing, terrifying guilt of egregious sin and intentional transgression (Psalms 32, 51).
David also experienced the exhilaration of deliverance (Psalms 18, 34), the joy of thanksgiving (Psalm 145), and the wondrous blessing of intimate fellowship with God (Psalm 15).
A careful study of the Psalter is incomplete without making this obvious observation: One of the fundamental messages of the Psalms is that no matter where on the spectrum of human emotion you are—no matter how wonderful or dismal your present circumstances are, regardless of what season your life may currently be in—honestly and courageously communicate the contents of your heart to God.