Forgiveness: What If You Can't Forget?

What if you can't forget a harmful event that changed the course of your life? Can you ever forgive the person that brought about such an event?
Forgiveness is letting go of the hurt. It does not mean forgetting the hurtful event. To “forgive and forget”:
Forgive your offender and you give him or her understanding and compassion.
Forget your grudges, hatred, and vindictiveness and you get happiness and peace.