How do I overcome shyness and build confidence?

One of my worst fears is not being liked. As a child I was made fun of, and I'm afraid of that happening again. This causes me to be inhibited and shy when around certain people. Or else I just feel awkward and not myself. I develop a different personality and keep walls up to protect myself. I really hate it. How do I stop being shy and develop true confidence? How do I overcome my fear? I've heard sayings like "not everybodys going to like you, oh well" but it doesn't help me much. Thanks.