It is easy to feel angry toward someone who has treated us unfairly or unjustly. Remember that God is watching over you and He notices when His children have been wrongfully treated. Be assured, He will make things right. In Romans 12:19, the Bible says, "Beloved, do not avenge yourselves, but rather give place to wrath; for it is written, 'Vengeance is Mine, I will repay,' says the Lord." Let God carry the anger and the bitterness and rest in the fact that He will see that justice is carried out. Do not let the enemy of your soul cover you with a blanket of bitterness. Every morning, throw that blanket off and rejoice that there is One who will take care of you. Choose an attitude of praise and worship instead of resentment and anger.
For He Himself is our peace, who has made both one, and has broken down the middle wall of division between us. Ephesians 2:14
Let no corrupt communication proceed out of your mouth, but what is good for necessary edification, that it may impart grace to the hearers. And do not grieve the Holy Spirit of God, by whom you were sealed for the day of redemption. Let all bitterness, wrath, anger, clamor, and evil speaking be put away from you, with all malice. And be kind to one another, tenderhearted, forgiving one another, just as God in Christ also forgave you. Ephesians 4:29-32