Here are ideas I've played with on how to respond:
"I've thought about what you said before you left. I've decided it won't work for me. I'm not willing to live in an open marriage while you date other men. From my point of view our reconciliation has failed, and I need to end this marriage. Will you join me at <mediator's> office to get our legal agreement wrapped up? No more anger or resentment, let's just see if we can work out the final details. We were almost there last year. I won't agree to anything less than 50/50 custody though, so if that's going to be an issue, we might as well not waste our time. The court will have to decide that one."
If she backpedals, and indicates that's not what she wants, I know myself, and I will feel compelled to offer her something. How should I handle this? I could just buy a little time and say "I'm leaving for a week, so obviously nothing is going to happen right now. We'll talk when I get back." Or should I just put up a wall and say "You've been right all along W, it just won't work between us. It's time to finally end this."
Ehhh. Lots of good meat in there, but tactically, it blows.
I really like your opening, but then I don't like it how you "assume the negative," at the point I've highlighted above. And then you've got it where, as you say, she DOESN'T want that, she's going to turn it back on you.
I would prefer something like:
"I've thought about what you said before you left. I've decided it won't work for me. I'm not willing to live in an open marriage while you date other men. If that's what you want, this isn't going to work, and we need to make arrangements with a mediator and we can work out the final details. We were almost there last year. I won't agree to anything less than 50/50 custody though, so if that's going to be an issue, we might as well not waste our time. The court will have to decide that one.
"I'd appreciate a quick answer on what you'd like to do -- no later than Monday. I'm sure neither one of us want to drag this thing out any further than we have to; Life is short."
