Notice that Jesus doesn't command us to feel like we should forgive. You can't command feelings. If we wait till we FEEL like forgiving, none of us would ever do it. In your will recognize the hurt and your response of rage or resentment or whatever. Then recognize the need of setting a goal of forgiveness, of releasing that response into the hands of Jesus.
Forgiveness needs prayer.
As we begin to recognize the violations, we begin to take them, piece by piece to Christ in prayer. We bring them to him who has first forgiven us. In prayer we acknowledge the hurt we feel, the pain, the desires for revenge we have against that other person - lay them all out on the table before his heavenly throne. Perhaps we may even want to write a letter to Jesus. Putting it down on paper sometimes is a big help.