@A-B Accepting responsibility for your actions and accepting that you were wrong does not mean that YOU are a horrible person, or that you shouldn't attempt to speak to anyone. That's catastrophizing, and it won't help you.
You really need to seek out pro-bono online counseling or consultation with a professional. There are peer support groups online that are specifically oriented towards helping you through those feelings. This is not one of them.
But: Accepting that you were wrong, does not mean accepting that you will always be wrong. It also doesn't require someone to spell out to you exactly how you were wrong, any more than getting a puzzle wrong means that you can never solve the puzzle unless someone specifically shows you every step. It just means you have to take a deep breath, realize that whatever you did then /wasn't/ working the way you wanted it to, and then, next time? Do something different.
I'm not on the game in question, but I'd imagine that your stated action of "I just got despondent at incredible length." made players and staff deeply uncomfortable, and they decided that they did not want to play with you. So don't do that again. You've been told that trying to pursue a conversation with someone about your banning or your behavior is wrong, so don't do that again. Keep a list if you need to, and consult it when you wonder 'what should I do differently'. Observe other people in social situations online, and see the reactions that various methods of presenting yourself gains. Even if you don't, in the beginning, understand /why/ these reactions vary, you can develop an idea of which outputs lead to which reactions.