You can find a Psalm for every feeling, emotion, and situation in life. The difficulty is tracking them down. Here's a way to find Psalms that speak to your specific situation:
Wisdom Psalms
These Psalms teach you true Wisdom for life and salvation.
These Psalms are About Creation and the origin of Man.
8, 19, 104, 139
Psalms of Zion
These Psalms are about God's people and church.
46, 48, 76, 84, 87
Liturgical Psalms
These Psalms are about worshipping God.
24, 66, 107, 118, 120–134
(The Hallel Psalms — 113–118 — were sung at the Passover meal and at other major festivals.)
Psalm 22
Most psalms fit neatly into one category. But Psalm 22 is in a category of its own. It's a Psalm of lament, trust, praise, and a Messianic psalm all at once.
It starts by saying: "My God, my God, why have you forsaken me?" These are the very words of Jesus from the cross (Matthew 27:46). And then, what follows is not just a general expression of suffering. It's the very passion of Christ in specific, almost clinical detail: mocking crowds, bones out of joint, a heart melted like wax, hands and feet pierced, garments divided by lot. And none of this was written after the fact. David wrote it around a thousand years before the crucifixion.
Then the psalm changes. It moves from desolation to deliverance and finally to praise. And then, the psalm ends with the declaration that people who haven't even been born yet will hear what God has done.
Psalm 22 is often called "the Fifth Gospel," after Matthew, Mark, Luke, and John. It's the gospel in miniature: death, then resurrection, then the proclamation going out to all nations. This is the heart of all the Psalms. And it is arguably the single most important psalm in the Bible.