Why one should forget one's mistake?

Are you talking about self-loathing?
Self-anger?
Depression?

Self-anger?Depression? All of these are related. I am trying to find out reasons how and why people forgive their mistakes because I find it is difficult to forget mine. Since it there are mistakes, the damage is done, why forget about it. I am trying to get myself get out of the hook.

step back a bit and be honest with yourself.

you cannot go back and change anything. ever.

(it's against all the rules)

all you can do is learn and understand the whys and hows of those bad things, and incorporate that into how you approach life from here on.

(the future is the only part you get to influence or change. try to focus there instead of mulling about with things that are dragging you down)

One shouldn't get angry at one's mistakes. One should learn from them assuming they are recoverable from which the vast majority of mistakes are. And the few that are not are what they are.

You must forgive yourself for your mistake.

Was anyone else hurt by what you did?

The mistakes I am carrying with me all my life are the mistakes I made when I was a teenager, while I was good at school, I gave up study to join the cools, and get myself in trouble and was labeled as one of the useless ones in school. One day we were in big trouble, someone was hurt but it wasn't me causing this but I was near the person when it happened. After that, I decided to turn my back from the cools to be a good person. That's one mistake.

When start working, I found myself quite inadequate doing things as I forgot all about my intellectual side of me. I made lots mistakes when I try to learn to do the job. I lost my confidents as a result I couldn't get the job done right. Now all the can remember about those experience are the mistakes rather the skills I have learnt. I have now a degree holder but I can't bear with mistakes. Those memories of the time when I made those makes are quite vivid to me all the time and as a result I can't think right and function right thought I am now well train to do certain job well.

College grade shows I am capable of doing thing but I can't feel it at all. Rationally, I think this is ridiculous, but my heart is not telling me the same thing. This really hurt.

Another one,

The "mistake" you make is not giving yourself a break. You must learn to forgive the feelings of your youthful faults. Mainly because they are following you today.

Be the adult now. Forgive yourself as you were as a child.