wow, movinon. Sounds familiar...I'm a teacher, my exN makes 4 times what I do (and hides most of it in another country now).
I could share horror stories, but I heard sooo many of those, and I bought lots of it, which energetically, I totally believe, kept me a prisoner in my own mind. (it's always in our mind).
It's hard to get prepared, legally and emotionally, for what you know will be a tough road, when what you also need is to stay with good, positive intention and energy in order to truly create the life you deserve.
How old is your child/ren? If they are older, consider (seriously) walking away. But I gather (sorry if I forgot) that yours are young.
I think you are smart to go for a psych eval....wish I had done that off the bat. I was feeling "guilty-ish", as 13 years of emotional N abuse is hard to break, so I felt bad and DIDN"T hire a shark, didn't want to "take the kids away from" him (when a little more control on my part would have prevented the present legal situation). Shoulda/ woulda, had I known what I know now....
Also....don't just go with the first lawyer you talk to. Take Hoppy's advice about seeing all the sharks so he can't...it's sound. See a bunch, however I don't know if it will all be free (around here, it's a couple hundred just to talk). It would have been worth 10 times that considering the huge financial hole that was created by my case.
So get the lawyers who will make HIM sick of it. Get a nasty lawyer, or at least a VERY smart one. I got a "nice, do the right thing type" and frankly, they still take your money just as well.. without necessarily doing "the right thing".