Tobias, you've certainly expressed some great DB'ing techniques here and it sounds like you're doing fabulous at listening and validating, so well done!
But like TXH said, there seems to be a big unknown here, the elephant in the room is whether she's still in an A or not. I know you said you didn't want to give her an ultimatum, but you also said something along the lines of her saying that "she knows what she needs to do". Meaning she knows she needs to go NC with OM, but she's not willing to do that yet. So there's still some cake-eating going on there.
Maybe the counseling is getting through to her, clearly she was expressing guilt about what she's done so maybe she's starting to own that. Hopefully with time and IC she'll get through it and recommit to the M.
But until then, your best bet is time and space and GAL. It's hard to tell since all we can see are your posts here, but are you feeding W a lot of time and attention (bad) or are you giving her space and GALing for yourself (good)?
