I still think there may be an element of truth to what I posted. Take it FWIW, but if you're right, and she's reserving the avenue of "going to him", then that's her plan "B".
She's still in C. She's still working on your R. She said in C that she wants to "feel in love" with you again. If that works out, then OM will revert to a friend. That's plan "A".
So long as she sticks to plan "A", her perception will be that OM is not a threat to you, and your concerns are unfounded.
I'll go with Rachael. Keep on doing what you're doing, and your W will stick to plan A.
As to the control issue... It's a sad fact that whoever wants the least out of a R has control. I agree with Kent insofar that control of the R doesn't mean control of you unless you let it.
But having said that, I think that when our S perceives that we are/were controlling, our first 180 must be to relinquish all control.
At some point, however, the power struggle has to stop. Step one, as I mentioned is for you to relinquish control, thus removing the threat to her independence.
I don't know how to get step two, which of course, is when you can start negotiating. I suppose, step two can only happen when the SO decides to let it happen.
You and I have both been following this path, Z. We both have to stick to it.