The worst mistake I ever did was, I believe a close friend who now perfidious.i learn a lot from it, a good friend that never leave a friend in whatever circumstances, I remember once when he came to me for help, I did it with sincerity without expecting any reward, but when I lost my parents and really need a friend, he did not come in the circumstances I feel sad, I hope to god that he does not do the same to my friends or people he met again.