I understand that it can be difficult to overcome timid, reserved, quiet nature (been there, done that, but it's a good thing to do). However, many actors are shy people, not necessarily incredibly sociable or extroverted, but still they're amazing because acting is faking it. Yes, there are technical elements and it is one of the most beautiful arts of all, but ultimately a good actor is a good liar with the uncanny ability to get inside absolutely any character's head and fully embody that persona. An enjoyable challenge.
After all, many aspects of life are false, particularly beauty. Nails, hair, tan, makeup - it's all one grand façade. So perhaps, deep down, everyone's a bit of a Thespian.