GB there are obvious arguments for why you should drop all R talk and pursuit (and R talk is usually pursuit). Normally, that's what we would all urge you to do, back off & give her space, etc.
But you have some unusual factors. You are about to move overseas, AND you know she wants something that is pretty much a dealbreaker. You have since been clear that you do NOT want her with OMs/OWs nor do you want to be with OWs...In other words, like most of us, you want a marriage in which partners keep their vows.
But she is being clear that She wants Other Men (AND OWs as options) AND if you won't let her get what she wants on this huge matter, she says she's done and the marriage is over... (But If you do grant it, isn't the marriage over anyhow?)
I suggest you put the fantasies of how this might work where it belongs-- in some Penthouse Forum article. It's not going to work that way in real life and not with your wife.
There is nothing to suggest she'd suddenly be interested in intimacy with you based on her being intimate with other men/women. (On the contrary...)
In essence, she wants you to financially (& emotionally??) support her exploring relationships with other men and women, while she's not being with you, & you are her h. 90% of women cannot have sex with partners and NOT get emotionally involved so...the saddest part is, that if you cave in b/c you fear losing her otherwise, you'll probably lose her anyhow. Plus-GB, I don't know what that does to a man's self respect. You are allowed to have some.
Option 1 So do you keep putting off dealing with the elephant in the room 'til you're both overseas, and stuck with more complicated issues of logistics...?
OPTION 2 do you plunge ahead talking more R talk now, without a 3rd party counselor to moderate (since SHE refuses that too) and hope she somehow agrees to stay faithful? And means it??
Option 3 Or do you calmly explain/SET YOUR newly discovered, healthy boundaries, and then live by them?
I don't know how you can cope with her Overt rejection, let alone all these other obstacles. But hiding from the issues & enabling her to mistreat you cannot be the solution. Part of me wonders if she just wants you to bail on the marriage, b/c this situation would simply be untenable for most men (and women).
It's very unfair and hurtful.
But only you know what your fears are, and what you can take.
M: 57 H: 60 M: 35 yrs S30,D28,D19 H off to Alaska 2006 Recon 7/07- 8/08 *2016* X = "ALASKA 2.0" GROUND HOG DAY I File D 10/16 OW DIV 2/26/2018 X marries OW 5/2016