Many times He allows disappointments in our lives with the intent of drawing us closer to Himself. Prayer is the most powerful tool a believer has. Nothing compares to it. Although I have given you examples from the Bible to make prayer, don't worry about what to say to the Lord. The Holy Spirit will show you.
Tears are just as effective as words at times.
I have learned that God is sensitive to every tear we cry. Just as He listens to the hurt you feel, He also knows how to deal with and guide you through any anger you are experiencing, regardless of where the anger comes from. It allows us an opportunity to tell God that we have been offended but that we are willing to give the entire matter to Him and allow Him to deal with it accordingly. He knows the way before you, and ONLY He can guide you through the difficulty. Always let your first response to trouble should be go to Him in prayer.