I think one thing to help with gaining strength on yourself is to always have a growth mindset. Meaning always be looking for ways to grow. Whether that be starting your own business, reading a book, going to the gym, learning about social skills, etc. Then at the end of the day, you know that you are expanding as an individual rather than getting smaller and retreating into your shell. So get out and push yourself to speak, but if it’s a really tough speaking day, then grow in other areas.