I don't know if your W understands what it means to affair proof the M. I leaned through my own experience that knowing you trust each other, is not enough to keep you from stepping over the line into that inappropriate area. Claiming to like men more than women for friends......is not good enough. Claiming to not have hung out with very many since the A (boohoo).........is not good enough. The fact that one or two other women are with her and the attractive doctor while they drink.......is not good enough. Is it? Did she do this long before her A, or has it started since the A?
Your W is either insensitive to your pain after her cheating, or she is not behaving like an educated woman who has learned from experience how to affair proof the M. What will it take for her to realize she cannot repeat similar scenarios, without the high risks? Maybe the MC is failing to talk about that part. The spouses have to affair proof their MR as much as possible. Sounds to me like the MC has not addressed what clear boundary lines look like in a MR after an A.
It is not about what you feel should work in your M. It is about doing the work that gets the right results. Do what works!