Well DNQ: This just sucks. Her behaviour goes above and beyond ANYTHING that a responsible mom would do. But contacting her is a waste of time - obviously.
The best advice I can give you it to journal. Write down every detail you can. You WILL need this information when you go to the counsellor and when you go back to court.
But don't call her lawyer. He will not help you. It is his job to help your wife.
Do the best you can do to protect and care for your children. If you are ever in a similar situation again, it would be best to stop the sitter in her tracks and tell her to talk to you calmly and away from your kids. Easier said than done, I know.
This situation is beyond hostile - it is extremely volatile. Again, I repeat - DO NOT CALL YOUR WIFE. Call your attorney. That is what you pay him for. Ask him how to handle things.