I usually have trouble contributing to a conversation in a group unless I'm directly addressed or I know everyone in the group really well. I had less of a problem in an academic environment because I've always been academically gifted and can imagine my contribution being worth something. In a social group, if I speak, someone may accidentally speak over me or not acknowledge that I just said anything and it's just confirmation that what I say isn't important and I'm not worth anything. Made me into a good listener though.