Carol, your experience with taking the combination of these drugs already speaks against an interaction of any significance. If there was one, it would just be as if you took a little stronger dose of Xanax than you really did (that's the objective view), but subjectively, you probably wouldn't even notice.

Some people do get depressed from benzodiazepines, but that isn't because of interactions with antidepressant meds.

I'm sorry you haven't yet hit on an optimal treatment regime, but I wouldn't be blaming drug interactions for the lack of success in your case.

Best,
Lar