I'm sorry you saw your W fucking your friend. As awful as you feel, note you can recover, whether you D or R.
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I find a number of ideas expressed in this thread to be unconducive to recovery, and I believe recovery has to start (and continue) before one can successfully R or D. Note that it's the ideas that I object to.
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A reco: Make healing yourself a goal. You can control that. You can't control whether you D or R - your WS can have an effect on that decision, and you can't control her. All you know is that you can't trust her now.
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My reco is to start with yourself. No matter what, D & R are extremely difficult. If you figure out what you want and go for that (or as close as you can get) before choosing D/R, you'll make your path a little easier. A good therapist can help you figure out what you want and perhaps make good guesses about the likelihood of achieving it. Knowing what you want helps recovery, though, even if it's unobtainable.
At this point, all you know about your WS is what she says, and you can't trust that, because your best bet is to assume she's working for herself, and she'll choose what's best for herself when and where that conflicts with what is best for your or your M or your kids.
So start with yourself and what you want. If you want D, you'll save yourself a lot of time and energy by making that clear now and going for D directly.
Whatever you do, make your decision from your strengths. Don't let fear drive you. The fear is usually of the unknown, and the only way you can deal with that is to out it aside, because none of us knows the future. A good therapist can help conquer fear. Remember: courage is saddling up even when you're afraid.
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A good MC can help. Most MCs use a system-based approach, and that won't help you, but some MCs will help you deal with the A first. Some MCs will hold the WS to account from the start, and they'll keep you talking about the A until you're done talking. That type of MC can help you a lot even now.
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There's no magic timeline for deciding between D & R. For me, committing 90 days from d-day worked fine. Others needed or took longer. Remember: If R isn't working out for you, you can call an end to at any time.
You're making a decision that will impact decades of your life and those of your kids. It's worth taking time to figure out what you want before acting.
'Ready! aim! fire!' is more likely to end up well for you than 'Fire!'
If you want R, my reco is:
Start R only if your WS is as committed to R as you are.
Start R only if your WS is committed to doing the work necessary for changing from cheater to good partner.
Start R only if your WS commits to becoming honest - no more lies, answers all your questions.
Start R only if your WS commits to keeping you informed of activities, companions, and locations at virtually all times.
Start R only if your WS allows complete access to personal electronics and digital activities.
If you want R, develop your own requirements, and end R if your WS doesn't follow through on commitments.
And Remember: If R isn't working out for you, you can call an end to at any time.
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So many betrayed men take the unfortunate path of trying to put the M back together at all costs….
Note that returning to the old M is returning to an M that has known vulnerabilities to infidelity. My reco: Go for a new M that’s better than the old one. Some people believe that's unattainable; others say it is, but it takes work and some luck, too.
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the "successful" betrayed (that is, those who come out the best after having been subjected to this living hell), are unanimously those who take a strong, decisive path....
The decisiveness that works best is being true to yourself, being honest with yourself and others, finding your own way through this.
It's best not to react; rather, it's best to make conscious choices. Wanting to beat the shit out of your (ex-?)friend and/or your W makes perfect sense. Deciding not to also makes perfect sense.
Wanting to control the sitch is normal - but it's best to realize you can control only yourself.
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Demand she WRITE a FULLY DETAILED timeline. Tell her she has 24 hours to write EVERY interaction, every text, every feeling, who said what, who initiated what, every sexual innuendo, every sexual act they did, along with the when, where, how, etc. ... if you discover she’s not disclosed 100% the first time, it’s game over and straight to D.
I couldn't do that for today's interactions with my W.
This is not how people think, remember, or write. That's recognized by the later direction to give your WS at least 2 more chances to add to the timeline.
IOW, don't set requirements that can't be satisfied. Be honest about what you ask for.
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Then tell her she will pay for and sit for a polygraph where she will be asked to confirm the timeline as 100% accurate and 100% comprehensive for everything that happened.
No one can be sure a TL for an A is 100% accurate and complete. The only honest answer is, 'No.'
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I would tell her that you are initiating D.
This is controversial, but I disagree with this for a few reasons.
Above all, I believe the BS's healing is the paramount need after being betrayed, and even just filing for D is an unnecessary complication unless D is your intention. If Unthought does this, he's going to have to divert some energy away from healing and gathering the documentation for filing. No one needs that when buried in the pain of being betrayed.
There's no way of knowing how Mrs. Unthought will respond, but the odds are that response will distract from Unthought's main task - healing.
Third, why pay the price for filing, especially if you have to find an attorney, unless you mean to D? Filing jsut in case sounds like filing out of fear. Filing as a tactic is - sorry - weak in the extreme.
If I need to file to get my W to get straight, I can't possibly think her decision is reliable. Besides, I wanted my W to choose me freely. Putting something she can see as a gun to her head is the opposite of giving her a free choice.
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Insist she informs both of your families of exactly what she’s done.
If you decide on R, this is likely to make R more difficult than if you've kept it private. By all means, share with people you want to share with. By all means, protect yourself.
Sharing the infidelity, however, is no protection IRL against being accused of DV. Some people make false claims of DV, but I suspect it's mainly from people under extreme stress ... perhaps from a woman under threat of a D that she doesn't want.
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Tell her it’s ON HER to "fix this". You will NOT be feeding her books to read, therapists to work with, etc.
The problem is that it's not the WS's to fix.
The WS is definitely is in charge for their own healing. To R - just to live a good life - the WS needs to change from betrayer to good partner.
But the BS has a lot of work to do - on themself. Without doing that healing, the BS can't really heal or R. If, as asserted in the quote, it's on the WS to fix, the BS has to follow the WS - but I keep asserting that the BS is better off following their own path, irrespective of what the WS does.
Sure, I'd advise a BS with an unremorseful WS to D, but I'm also for the BS D'ing if the BS wants to D/if the BS simply doesn't want to spend the rest of their life with the WS no matter how remorseful the WS may be. (That's buried in words somewhere, but there general principle of stating the onus is on the WS should never have been stated that way.
And R is a cooperative venture. The new M has to serve both partners. That means both partners need to make their wants known and make conscious choices about how they'll get what they want form the new M.
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I would ask her to go live elsewhere....
Yes, the WS is a trigger for a BS in R, but separating has some disadvantages.
First, IMO the BS needs to communicate a LOT with the WS to gather the info necessary for the D/R decision. The non-verbals say more than just the words, and one doesn't get the non-verbals except face-to-face.
Second, since R is likely to involve living together, it's best for the BS to test their ability to live with the triggers.
Third, if R involves living together, separating while deciding means making the decision while living in an artificial environment. IMO, it's much better to start as one hopes to end. If one hops to end living together, live together to see how it works out. Otherwise, separate.
Fourth, a remorseful WS will provide triggers but will also provide support. If you're separated, that support may not be available when one wants it. It's easier to wake a partner up in the middle of the night than to clear one's head to make a phone call. It's also easier to take in support when you're next to each other than on the phone. It's easier to get back to sleep, too.