rightly or wrongly through what i know of my sitch, my gut feeling GUESS is that W has had an affair of some kind/duration. i spent a good bit of time reading up on the why's of affairs and learned a great deal. the need for validation of looks, feeling alone, being resentful, lots of sex, etc many reasons that i could see in my W. and then, more importantly i could see how what i did not provide could have brought about those feelings in my w. not getting away from the tv, basically just not giving to her the level of attention she may have needed. i know to separate the issues of the marriage from W having an affair IF she did, but i did and can see how the discontent from the MR could enable W to have an OM.
Ballast, you're telling yourself stories, then getting spun up about the stories you're telling yourself.
You don't know if W had an affair.
To spend so much mental energy playing the "let's assume that W *did* have an affair, and then explain why she chose to do that, and compare it to my reasons for why I didn't do that" game has no value other than torturing yourself with useless speculation.
There are facts, and then there are the stories we tell ourselves, which are not facts.
The fact is that your W decided she wanted out of the relationship, and another fact is that since doing so, she has not been communicative.
The "why" behind her actions is likely forever out of reach. Even if she eventually tries to explain to you why she did what she did, it probably won't be accurate because it will be clouded by how she later comes to look at her past, which is often inaccurate, its a narrative that fits prior behaviors, but isn't the real explanation for them.
I would submit that this ---^ is the real problem that you're having. You can't explain W's "big why" and because you can't, you feel terrified that you won't be able to prevent it from happening again, or predict if it might.
Coming to terms with this -- the fact that you can't predict, anticipate, or control what other people decide and that the rug can get yanked at any time is a major thing to comes to terms with. It's a stressful process of acceptance. Once you get there, you realize that all you can do is control your own behavior and live with integrity. If you do that, you'll come to a "if someone wrongs me it is their loss" philosophy which will give you great comfort.
Regarding your hypothesized affair, the counterargument to that would be that someone with generalized anxiety disorder lives in constant fear of what could go wrong. Their anxiety leads them to be distrustful of others and standoffish. Someone who is suffering in that way would be unlikely to want to add the additional stress of deception and ultimate risk of being found out and humiliated. If anything, your wife's exit from the relationship may have been an attempt to have "less to worry about" which would be a rejection of relationships in general in order to ease her anxiety disorder.
I'm not saying that's what happened, and maybe she *did* have an affair, I'm only suggesting that her behavior can as easily be explained by a "no affair theory" as it can be by and "affair theory" so its not really worth your time to play out and dissect either one.
Married 18, Together 20, Now Divorced M: 48, W: 50, D: 18, S: 16, D: 12 Bomb Dropped (EA, D): 7/13/11 Start Reconcile: 8/15/11 Bomb Dropped (EA, D): 5/1/2014 (Divorced) In a New Relationship: 3/2015