a bad thing a bad our brain, is it distorts and deletes information.
what does this mean ?
basically, what you dont want to see and dont want to hear, your brain blocks them off automatically.
and, what you have done that you dont like to remeber, your brain deletes it!

thus many times when two people are in the exact same situation, they experience an entirely different thing.
finally, you will also find yourself being unaware of some of the things you said and did, because your brain deletes them.
for example, if you strongly believe that you are an honest person, on a certain occasionan you lied. you will quickly forget about it and continue believing that your completely honest.
but who can say for sure that he is completely honest?

my point here is, its great to have friends to act as mirrors, showing you and telling you
what you have done and giving their perspective.
only then, can you improve the man in the mirror.