We seldom if ever, develop beyond the stage of pupil, and like Paul, we must learn to die daily. Not only does our spiritual welfare depend on a forgiving spirit, but the one who has offended us is dependent upon our forgiveness. By acknowledging feelings in our heart. Confess these feelings to Christ, and in many cases verbally express forgiveness. The feeling of forgiveness is a process that may come much later than the actual point of forgiveness.
Some wounds take time for healing.
But forgiveness is assurance of poison being removed from the wound. One moment in God's eternal bliss will erase any hardship or hurt anyone could ever cause us. And honestly, I can't think of one person or situation worthy of unforgiveness that is worth losing my victory over.