No one's suggesting that you are a problem client (other than the fact that you raised the idea of being "black listed," which I may have misinterpreted). We have no idea why you're having trouble finding a lawyer.
As far as the duty of confidentiality, OPPOSING counsel owes no duty to you. I submit that it would be seriously frowned on, but probably isn't expressly prohibited, for opposing counsel to contact a lawyer you're considering hiring and talk dirt about you. It would be unlikely that a lawyer you're considering hiring would contact opposing counsel for any reason. So, again, we can't tell you why you're having trouble. What we can do, however, is suggest that some reasons simply aren't illogical.
With respect to "black listing," I thought you were talking about your former lawyer(s) saying you were a problem and discouraging others from taking your case. On further review, I don't think that's what you were saying. Nevertheless, the conclusion is roughly the same.
"Rules of confidentiality mean nothing if opposing counsel is allowed to paint me as a problem client."
Rules of confidentiality don't have anything to do with you and opposing counsel. They relate to your relationship with YOUR lawyer or lawyers you might be considering hiring.