Marc,
It's apparent to me that you have a good understanding of your situation...but need input to clear up some doubts and fears, perhaps regain focus. There are many layers you are trying to work through...

Please consider starting therapy so you will feel somewhat comfortable with the therapist before your wife returns. When she does return, it may be that you will be more prepared for it.
It's so very important for you to take care of yourself.

Couples therapy is challenging but rewarding as I'm sure you know. It's a good way to negotiate, compromise, and re-establish honest communication.

In many ways, your frustration and hurt are showing...and you have every right to feel this way. The woman you love is hurting herself and you...finding ways to change this is going to be complex. One thing at a time is hard...
I'm glad you have a pdoc and are knowledgeable about the medication side effects. Would your pdoc recommend therapists that he/she knows are well qualified in their fields?

My best wishes for you to get the things in place that you need so the two of you will be content more times than not,

In Peace
Catherine

jmo