I've recently been through a break up and my boyfriend Peaches helped me to deal with it. I was ABSOLUTELY devastaded. I'm sure Peaches had a hard time helping me with it, he confessed a lot of feelings on the line of "Am I not enough to keep her happy" and "How COULD that childish, selfish person do this to her?"
I'm now getting back togheter with CC, the guy who broke things up earlier this year. CC is both younger than me and Peaches and very new to poly. He had never even considered it before. He didn't know about the term "monogamous" and that there were other ways to live life, for f*** sake. He's REALLY green on relationships in general.
Of course poly spooked him out at first. To me it's understandable. Even if he did hurt me when he said he couldn't do it, even if I spent months as bad as can be as a result of that break up.
To Peaches, on the other hand, his behaviour was unaceptable, childsh and, yes, fickle, since he now decided he would like to try this again.
Maybe it's because I love CC and I am emotionaly tangled in this and Peaches isn't. But Peaches did understand, in the end, that this is something I REALLY want to do, to pursue this relationship with CC. I still find myself defending CC sometimes (Peaches has taken the bad habbit of making sarcastic comments about me "adopting CC" or "CC needing to get his glass of warm milk handed to him every night), but actually, CC is doing a lot better this time around, he's trying hard to warp his mind around poly and we're happy.
So I just wanted to say that if your wife thinks it's worth the chance, and you decide you're really ok with poly, support her on trying this out one more time. She felt the hurt of the break up, she should be responsible for the risks of trying again. You'll be there for her in case thing go wrong again. (I would just advise her to make sure this break up/trying again thing doesn't become a cycle.)
As you experienced yourself, poly is kind of hard at the beggining. And this for a couple already considering it and researching, already feeling safe and confident with each other. Aking for someone to just dive head first into that and not even flicker is a lot to ask.
Me, female in a V with Peaches, live in boyfriend and CC, boyfriend.