When you get to the point of feeling there is nothing else you can do, that's is God's opportunity to work.
I've been a Christian since I was seven years old when I accepted Christ as my Saviour. In all of those years with each storm that came my way, I can't remember God ever telling me, "Just relax." However, I've heard Him many times says, "Trust me." I may writhe my hands wondering what could be coming next, but when I sense God saying, "Trust me," I begin to rest in His presence and His care. When I let go of my need to fix my own problems, He handles all of the details of my circumstances perfectly.
David placed his hope in God and not in his own ability as ruler and king. Psalm 55:22 says, "Cast your burden upon the Lord and he will sustain you; He will never allow the righteous to be shaken." The word cast here literally means to "roll over to God". David is urging you and me to roll the burdens of our hearts onto the Lord. He alone has the power and ability to handle it.
When the skies seem to darken and sin and hopelessness gather around you, ask God to reveal Himself to you; and start rolling!