You appear to have little confidence in yourself and that is the fundamental problem. You are seeking direction from people who cannot understand your problem

You appear to have little confidence in yourself and that is the fundamental problem. You are seeking direction from people who cannot understand your problem fully because it is internal. You are seeking instructions, solutions, answers and validation, all of which cannot take into account your key issues. Where you are in terms of your skills, or your professional or career success is basically irrelevant. You would do well to strive for whatever you wish to strive for, whether you get there or not. I would advise you to start a process that leads you to learn most about yourself as quickly as possible. Anything that turns your realisation inwards and shows you who you are will benefit you most. Do not run from yourself. Now, what you do could be varied. They could be to face your fears (e.g. toastmasters), or they could be simply a discussion with a friend who can help you look at yourself. The final decision about what you choose to do needs to be your own, for as is in your nature, you will always doubt whether you have chosen the right thing, and you will no doubt find excuses about why the advice you were given and attempted to follow might no longer be the right advice for you. Good luck. I'm pretty sure this isn't supposed to be easy.