David’s enemy and adversary is his own friend in Psalm 55. If it were an enemy, he could handle that, but a betrayer is something that creates such distraught for him. 

This betrayal turns him to God, and throughout the day David calls to him and puts the matter into God’s hands. 

Psalm 55 is but the voice of Jesus crying out that he has been betrayed by one of his own and how the betrayal hurts. But even in betrayal Jesus knows that God will do right by him and will lead him out as he faces all our foes.