the way to deal with it is by exposing yourself to social situations and just practice talking to people. its just practice and each time it gets a little easier until its easy all the time. dont worry about what people think because people are nice and nobody is judging you. besides, people will tolerate a lot of shit from people before being annoyed.
hope my random advice helps. i suffer the same problem and think i always will but its manageable. everyone is different and its what makes you special. sure, other people might seem super confident and stuff but they have their own problems.
theres more important things in life anyway than talking to people and when you feel insufficient in one area of your personality, you tend to compensate for it in other ways. for example, im sure you are amazing at something like music, art or maybe you are super intelligent at something?