I can totally relate to this. I'm in the exact same position as you. I've always been self critical even though others have always accepted me from my experiences. Its just so mentally draining trying to speak to people and doing the basic things. Today I had to take my baby to a baby sensory class and struggled to even say my name but I know i have to get out there for my baby's sake. I see it as if they judge you or make comments then they aren't really nice people. You'd be surprised that people don't tend to mind at all. By taking this first step it's given me courage to go and attend another class and try meeting more people. Hopefully by meeting more people I will gain more confidence to stammer a little less. You just got to take small steps in interacting with people