The thoughts/advice paradigm imparted are good; pay heed to them. There is merit in the idea of putting the poly relationships on hold in order to work on the original relationship, but, it's also hard to put any (even a poly) relationship into reverse; it's much easier to keep it moving forward. So, sympathize somewhat with your wife and shoot for a compromise. Maybe she could just slow things down while you and she work on your relationship.
It's really rough to have your sex life put on hold, especially if it's not on hold with the other guy. How long has this been going on, that your advances have been rebuffed? It sounds to me like she has some kind of deep-seated issue or resentment that is blocking her feelings toward you. A good poly-friendly counselor is definitely needed. It's good that she agreed to that, even if it was with reluctance.
You should sit down with her and share your feelings, such as how you feel about not being able to sleep with her, and again, try to work out a compromise. Remember, when you talk to her, you must be careful not to infer any guilt or accusations, lest she tighten up like a defensive fist. There is something going on with her that hasn't been spoken yet. We're just seeing the symptoms.
Sorry you are going through with this. Sometimes poly takes the lid off of problems that would have otherwise remained forever hidden. There is a chance you and she can grow closer, if you approach the problem carefully.
Please keep us updated on how things are going.
Love means never having to say, "Put down that meat cleaver!"