If you have made mistakes, even serious ones, there is always another chance for you. What we call failure is not the falling down but the staying down.
One thing about life that we must all come to terms with at some point is that not every battle we face will be one that we reign victorious in.
Just as a baby learns to walk, and stumbles and falls many times before they are able to really have enough balance to carry themselves by walking correctly, is how we learn different things in life, especially how to become a winner.
Overcoming our failures may take a very long time, and very large amount of tries, but if we are able to stay positive, and if we able to persevere through the most difficult times, the times where we see the result of our diligence and perseverance will be that much more worth it.
As long as you have breath in your body, you still have a chance to be a winner in everything that you do.
From your relationships with others, to things like getting a better education, you cannot fail until you quit trying!