That's about the best advice for life..
You should never give up because new opportunities come when you're least prepared for them.
There are a very few of us, who become successful on the first try.
If you're not one of them, just try again and believe in yourself and your abilities.
And I agree that you need support from people close to you, it's difficult to take on the world alone. You need someone who believes in you completely.
Just keep trying until something good happens and it will happen.