Blabbering about non-blabbering

There is this moment when people start asking questions, that I begin to not want to answer them. It's very strange, but sometimes I want to say something, but I can't, not because of the lack of listeners, but because I just can't. It's like someone is muffling my vocal cords.
It happened so many times, that I just avoid conversations that are too intrusive .

On another very different note, when is the Harry potter movie going to hit the cinemas? It's been over a month, what's going on here?