It is very true that the greatest enemy of somebody is himself/herself when forgiving oneself.

It's hard to forget the mistakes, sins, or offenses you have done to yourself and other people; especially, if you know that justice is overwhelming while mercy is almost absent. You wish it hadn't happen but can no longer do anything to get the innocent past back.

Clear examples of this are...
*when you broke a school regulation and may be a candidate for suspension
*when you lied to a considered friend and cannot get forgiveness
*when you have said a careless and hurtful word that wounded somebody else and he/she didn't forgive you
*when you could have taken care of yourself before you got sick

Forgiving oneself requires peronal and social mercy but, sometimes, it isn't just present. This may result to hopelessness in life, unwillingness to change, difficulty in moving on, and even suicide.

Justice protects and correction improves but only mercy can forgive and change. It just so happens that in a modern idealistic society, ugly consequences become the emphasis instead of the true change that they may bring to somebody.