I'm a pretty private person, so I don't reveal much about myself until I've gotten to know the other person over time. Maybe that behavior helps me build trust? I'm not sure; I'm not the best at introspection.
@Pokcare, does anything seem to help you? Maybe once people have proven themselves through their actions, you'll begin to lighten up. Don't be too hard on yourself. You've realized that there is a pattern to your behavior, and you're working to make changes, which is pretty amazing!