You don't need to apologize. I do genuinely appreciate your post and comments.
I do acknowledge that my decision to take a stand against this abusive individual is the catalyst, or at least the fuel for the latest blowup. I am so sorry that he has then gone on to abuse you after you tried to help him.
I guess my question is more for the broader SGS community. Is tolerating abuse what SGS is about? Because if it is then I won't be staying on in this role much longer.
Not at all. Abuse has consequences. Especially personal abuse should not be tolerated at all.