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I am trying to prepare for divorcing my wife of 4 years. She doesn’t know. We have 2 kids, of which i want custody. She has a history of mental illness which has resulted in our kids school (private) asking us to leave. She’s a disinterested mother.

I need to know what i should do. How should i prepare? I can afford a good nanny and legal fees, i need to win custody of the kids.

We live in Illinois.