Being ignored, especially in group conversation, which is almost an unavoidable reality considering my demeanor. Whenever someone talks over me or doesn't acknowledge what I said, it nearly always throws me into a rage, sometimes quite visibly.
I also dislike being criticized when I didn't ask for an opinion and the rebuttal that I should value the criticism anyway, as it can only do good. To me, that assumption is insensitive and disrespectful.