One thing that struck me about your post is the emotional rollercoaster being brought to the table. Coming home to tell you that she wishes that she married a doctor so that she wouldn't need to work is both mean and not entirely true. Many doctor's wives, at least many of the ones that I've noticed around here have wives that do work.

Maybe set a limit as to what is acceptable relationship conversation? For instance specific cause and effects with feelings.

Her built up resentment is hers to own and to sort through to find out what exactly it is that causes it.

Is she committed to working on this or is this just a waste of money in therapy? Will this couples counseling turn into her justification to say, yep, I tried, it didn't work. That's something worth asking.

"Interrogate your hidden assumptions."-Cornel West