Chris, I know just how that feels. The vast majority of the congregations I attended made me feel that way with the exception of 2. Especially this part:
Trying to be part of a conversation in a small group of witnesses and have someone cut me off in the middle of what I'm trying to say and continue on like I never even said anything. That always made me feel good...
Nothing says "You don't matter to us" like cutting someone off and continuing to talk like they're not there and are unimportant. I've experienced that more times than I can count! It gets to the point where you just say "You know what? Why do I fucking bother anymore?".
I really feel for you with the crap you experienced, especially at the hands of your parents.