"How long O Lord"? is found in Psalm 13. All of us who have called out to Him for help have uttered those words. Are your days long and winding? Is there a boulder in your narrow path that seems unmovable? Does your heart ache after repeated attempts to deal with that frustrating issue?
Jesus in His humanity uttered a "How long must I put up with you" at one point. He gets the frustration of this world keenly. So it is ok to groan and lament a difficult situation. God allows "how long" quite a bit in the book of Psalms. He gets us because as He told Jeremiah in the Old Testament: "I knew you before I was born".
So be real with God, owning your emotions. Tell Him what you feel inside. Ask Him plainly for help in your troubled times. But Psalm 13 ends in a verse of trust as well. Don't miss that. "He has dealt bountifully with me." He is not the parent who runs away from a fire, He is the Firefighter who runs toward it, and you.
"How long" is real to ask. But ask expectantly. Have the faith of a child who believes His Poppa will save the day. Be comforted today with this Hope!