say what I really mean when I want to say it

I always pass up the moment for me to say something…ALWAYS. Inside my head I am yelling at myself for not saying something while I could be saying it but I can’t bring myself to say it and when I do its never what I meant or was really feeling. For once I would like to say what I wanted when I wanted. Even if its like in the movie When Harry Met Sally and I come off as rude and mean, it would be a breakthrough.