Here is a quote worth meditating on from Dietrich Bonhoeffer on how we should learn to let the Psalms, prayers inspired by God, shape our own prayers:
“If we want to read and to pray the prayers of the Bible and especially the Psalms, therefore, we must not ask first what they have to do with us, but what they have to do with Jesus Christ. We must ask how we can understand the Psalms as God’s Word, and then we shall be able to pray them. It does not depend, therefore, on whether the Psalms express adequately that which we feel at a given moment in our heart. If we are to pray aright, perhaps it is quite necessary that we pray contrary to our own heart. Not what we want to pray is important, but what God wants us to pray. If we were dependent entirely on ourselves, we would probably pray only the fourth petition of the Lord’s Prayer. But God wants it otherwise. The richness of the Word of God ought to determine our prayer, not the poverty of our heart.”
Dieterich Bonhoeffer, Psalms: The Prayerbook of the Bible, 14-15.