Hi BJ, been kind of just watching your situation unfold.
First off, as hard as I know it was to do, I applaud you for having the strength to protect your children by filing first. I think if I had, my outcome would have been much different. (D'd with joint custody where XW is custodial parent)
Secondly, you may very well end up as the custodial parent if your retain the family's prmary residence. Judges now a days want to see the minamilist impact on the kids as possible.
Ultimately the question is how far are you willing to take the custody issue? I got within days of appearing for mediation with them, then having them go to court the following week, and I just couldn't do it. I just couldn't put them through that.
Now, here's what I've learned post tense.
My XW, much like your W had my kids singing the praise of OM. She up and left within a week of me confirming the A and despite my requests carried on directly in front of them. This in time, a year now, is getting old with my kids as they are getting older and wiser.
In turn, it's unfortunate that my XW now is begining to see the err of her ways. Of course now the excuse is we're divorced because I hurried it along and she wanted to drag it out, "to think".
So, learning from how mine sitch turned out, heed the last statement and maybe drag it along for a bit. Where will your W get financing to combat this? I would certainly tell her to leave the house immediately in light of the kids comments about OM. You could also file a motion for temporary and emergency custody while the D ensues and establish visitation restrictions, acutally I highly recommend it, and am surprised your attorney hasn't if infidelity is part of the complaint.
Those two combined may just be enough to give her a dose of what the reality of things will be post D.
So, that's just some ideas.
Take care and stay strong.
Me 35/XW 33 S13 & S12 M: 10/17/98 OM & S: 07/08 D final 06/09/09 12/03/09 - 06/13/10 "Piercing" 06/13/10: Engaged to Re-marry 10/17/10 06/25/10: Expecting baby #3 2/14/11