There really is no way to just "snap them out of MLC". They have to be the ones to travel their paths until they are finished. If you attempt to pull her back into reality, I can promise you that she will re-enter the crisis at a later date right where she left off and it will be far worse than it is right now. The best thing you can do is dig deeper for patience and keep the focus on you and your family.
When they see that we are not fighting the divorce and we begin the process of negotiating settlement, many will become very angry because they do not want to share anything w/us. They do not care if we have a roof over our heads or the children are well taken care of. They are very selfish and self-centered and basically want as much as they can get from the settlement. And, yes, they project everything on to us and we are to blame for all of their unhappiness, which we truly are not.
A MLCer living at home can be very trying. You may want to look up Hawho's threads. She went through the paces w/her man/child and ultimately he moved out and is continuing to be a PITA. They will most certainly try your patience more so if they are living under the same roof because you are around them far more than if they are out on the street living elsewhere.
The LBS will eventually begin to test the waters w/the MLCer, i.e., like a lab experiment and you will discover what works and what doesn't. At that time continue to use what works in your situation. No two MLCers are alike, but they sure do exhibit many of the same behaviors and say things that sound like they come out of a play book.
If you aren't in any hurry to divorce her, then sit back, watch the parade and keep an eye on your finances. Of course, keep the focus on you and your family. One last thing...be sure to wave as she zooms down the street. Try to remember, you didn't break her, therefore you can't fix her.
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.