Unforgiveness will ruin your day. If someone hurts you, pray quickly, "God, I forgive them in Jesus' name." If your emotions feel strained when you see that person, stand firm in your decision to forgive them.
Pray for them, asking God to show you how to bless them. Do whatever God leads you to do for them, and let God's love work through you to heal the rift between you. If you do your part, God will bring your feeling in line with your decision, and you will enjoy your day and your life.