KAW, would you please refresh my memory? What happens when you go a bit dark with your W?
I may not be seeing all of the options here, but it seems that there are only four likely conclusions to the situation.
1. She has an opportunity to find out what "be careful what you wish for" really means. It is so obvious that it she were suddenly fully available to have an R with the OM, she'd find out in a big hurry that he's a player who doesn't give a rat's pooter about her. I'd give it somewhere between 2 weeks and two months for him to show his true colors, busting her fantasy big time.
Very likely, she'd be clicking her heels like crazy, saying "there's no place like home"!
2. You do a last resort technique or finally grow sick and tired of limbo and initiate a separation. This action would wake her up in a big hurry! She might try option #1 if you force the scenario, but option #1 has only one likely conclusion.
3. You do nothing, and nothing changes. Even after the OM is physically out of the picture, she could hang on to the fanstasy for years, thereby ensuring she never risks real intimacy and vulnerability with you.
4. She eventually grows up and recognizes her BS as BS and realizes what she has put you through.
I don't know, KAW. At this point, I'm concerned about what is best for YOU and wishing you weren't being emotionally abused anymore!
