Forgiving your offender or defaulter doesn't only help him or her. Rather, it as well helps you that was offended to be at peace with your own self and most importantly with God. Yes you heard me right as usual. Besides, anyone who fails to forgive his or her fellow human is an enemy of God. And until he or she forgives his/her offender or defaulter. He or she will never be in good terms with God.
Forgiving yourself/ourselves gives you/us peace of mind and power/freedom to move forward and never backward. Yes of course, anyone who refuses to forgive himself/herself/others of his/her/their mistakes/offences/short-comings is unknowingly declining/degenerating morally/spiritually rather than increasing/appreciating.
From the Gulistan Be not over much angry with thy slave; Treat him not unjustly, and pain not his feelings. True, thou mayst have bought him for ten direms; But 'twas not by thy power that he was created. There is a tradition of the Prophet--peace be upon him!--that on the day of the resurrection the greatest grief will be when the pious slave is carried to Paradise, and his worthless master is borne away to Hell.
Gratitude unlocks the fullness of life. It turns what we have into enough, and more. It turns denial into acceptance, chaos to order, confusion to clarity. It can turn a meal into a feast, a house into a home, a stranger into a friend. Gratitude makes sense of our past, brings peace for today, and creates a vision for tomorrow.