LITB, stay strong in this. You might go through a multitude of emotions now. But through all this know that you are doing this so that the kids will have a better future.
When i told my wife about me retaining lawyer and that i'll be contesting her actions on child custody, she hit the ceiling and said a lot of mean stuff. It hurt like hell. But i did not back down.
Heads up. I am not sure how your wife might react. But in my case wife did not make it easy for me to interact with daughter. She did not prevent me from talking, but did not assist either. Hopefully it will not be the case with you, but just be prepared.
Believe me the initial wave will be hard. But one you dive in, relegate the harder stuff to your lawyer to handle it, life does become easier.
Good luck!
BITS M 38 W 36 D 7 Married 15 yrs W left for 6 months in 2009 W Filed for D 01/03/11 piecing now...