Ahhh, I can understand that feeling of being vulnerable or stupid. It can be hard to talk about things we've kept to ourselves for most of our lives. I must say though, your English is better than a lot of people I know who are native English speakers.

It's funny you say that about the need to say 'hello'. That's a massive part of the reason I don't like to be noticed at parties or functions. I spend days worrying about how to say hello to people. Do you simply say it and move on, do you shake their hand, what if they go to shake your hand and you don't notice and then they feel you've ignored them, what if you go to shake their hand and they think you're being too formal.... then panic ensues. I'm not a fan of bodily contact, I can tolerate it with people I know well such as close friends or family. But even then, I don't like too much of it as I just get a bit overwhelmed and uncomfortable. I also really hate the feeling I get if I think people are looking at me, which is why I'm generally pretty quiet, if I don't speak or say something stupid then I'm less likely to have all eyes on me.