I bet it was only you who thought you sounded rude and hostile; don't be too hard on yourself. I use to get in moods in both individual and group therapy where I couldn't/wouldn't speak and then get tangled up in how I couldn't/wouldn't speak. Sometimes when I get anxious or "stuck" like that I get angry to get myself out of it. Anger is motivating in a sense.

It is hard like sunrise says; hard to know when to jump in, when not to, what to do if you're bored or if the conversation is about subjects that are foreign or scary to you, etc. That's part of what one is supposed to be learning and when one is learning, one is a beginner and can't know it all instantly. It's not just moods; even my T confessed she had trouble with silence and knowing when to talk or not. How much harder must it be for us who have never learned the "rules" well/yet?