This might sound like a silly question but have you and your friend discussed having a romantic relationship ?
And have you thought about how that new relationship would fit with your current life ....time...and attention. Do you have kids ?
The counseling issue would seem to cut both ways you don't want to be judged and she might not want to be indoctrinated or lectured on fear. I can see there's no easy answer ....just pointing out the other point of view. Personally if I'm asking for the big change I might bend on possibly being judged ...or asked uncomfortable questions I can always register a complaint or quit ...at least I tried.
The picture Im getting of your wife is she's jealous ...insecure ....doesn't like to share...closed minded ...maybe stubborn. The new possible gf is poly already big hurdle removed ...already mentally on board.