Abbondad ~
First, keep up the good work...you've come a long way since I first started following your saga!
Second... What advantages to you see to Collaborative divorce?
From what I've read/seen/heard, they are more expensive than mediated divorces. It also requires the agreement of ALL parties (which your WW would NOT agree to at this point) to participate in a "what's good for the whole family/children" frame of mind.
I just don't see that happening with your WW, and frankly, I would be tempted (in your situation) to get something filed, especially with regard to custody/visitation.
State laws usually govern most of the divorce proceedings anyway. Unless your situation is especially complicated, there's not a lot to discuss.
Although most people don't think this is true, I'm a firm believer in being the one that initiates proceedings. Its MUCH easier to be in the drivers' seat than to be taken for the ride. YOU can initiate proceedings, specify financial/asset division, custody/visition and CS details. She can either agree (and sign on the dotted line) or not.
If the two of you have already discussed a lot of the financials/Custody/CS stuff, then you already know where she stands and I would strike while the iron is hot. There are GOBS of people who either trusted or believed their WS wouldn't screw them in the end....and of course, they did!
There are TONS Of posts here on SI regarding detailing custody, visitation and CS arrangements. Because I don't know your financial situation, I cannot speak to how complicated that may be.
I was a do-it-myself divorcer.
I filed the papers, did all the serving/required junk and made it happen. He didn't even have to respond at all ~ even though he agreed with it, it was filed as a default judgement.
Get your assets and salary/incomes listed, get your debts identified. Gather all your propety and tax information. Round up any pension/401(k)/investment account statements.
Continue to document all 'parenting time' arrangements to date (you've been doing this, right?). I'm thinking you've got a visitation/custody plan sorta, kinda worked out? Put it in writing! There are GOBS of details here about custody arrangements and child support issues that may arise in the future. Write it all out...and be SPECIFIC.
If your situation was *simple*, I would say to fill out the paperwork yourself and have your WW review it. See if she's REALLY going to be cooperative (or not).
But I don't give a flying fuck about your WW, and more importantly, I don't trust her.
I would take my info to the nearest SHARK attorney and file for divorce. You can mediate when/if she doesn't agree with the terms, but you CANNOT have a collaborative divorce with someone who doesn't WANT to, and moreover, REALLY doesn't have the 'best interest of the family' in mind.
I'd really like to see you in the driver's seat, Abbondad....instead of watching your WW take you for a ride. She is obviously interested in the best outcome for HERSELF alone.