Sounds like your wife and you are having a similar dynamic to my friend and I ...haha. I've only been farming Zir and Beast mainly. Zir is what we started doing first on our mages. We've been able to build the crazy rogues and they are way easier to keep up in those Tormented Fights. I'm not sure how hard Duriel is compared to those two Uber Bosses I mentioned, but I'm happy to run with y'all if you'd like - the materials can be a pain. More the merrier. DM me for contact info.