IMPROVE self esteem
Low 'confidence' or low self-esteem issues are best dealt with by a good counselor (or psychologist) who can find 'root' causes and help you gain confidence again.
One place to start is to recongnize 'the negative self talk' and change what you think of yourself. For example say to yourself 'i am a valuable person! ' not 'i'm can't be useful', etc.....And try to focus on your assets (many! ).