Sonja Lyubomirsky said this quote

a shift in thinking’ toward someone who has wronged you, ‘such that your desire to harm that person has decreased and your desire to do him good (or to benefit your relationship) has increased.’ Forgiveness, at a minimum, is a decision to let go of the desire for revenge and ill-will toward the person who wronged you. It may also include feelings of goodwill toward the other person. Forgiveness is also a natural resolution ofthe grief process, which is the necessary acknowledgment of pain and loss.

~ Sonja Lyubomirsky