Thank you all for replying.

Silence. I don't think really it is because I have a " feeling of being safer " when I prefer to stay silence and don't talk about my hurt inside. I don't have the impression that this is why I do this. It is more because I don't want attention on me, don't want people to feel pity on me, don't want people to feel I bother them, don't want to take the space that maybe someone else needs, don't want people to stop in their track just to help me out.

Maybe I simply don't want people to know. But why I do not want people to know? Good question! I don't know.