Look back to your life and learn from previous experience and when you see forward, keep hope. You see the reality when you look around. So what you need now is to look within and you will get YOUR SELF.
Always look for opportunity to learn from anyone to everyone as rightly said that nobody knows everything and everyone knows something. No one is born happy but it is an ability to generate happiness.
We never lose in any situation, good people give us happiness, bad ones give experience and the worst ones give us valuable lessons.
Always remain happy.
Always remember your failure is a proof that you are trying.....keep on trying.