I could not finish reading this thread because I'm busy but I might forget to come back to it. From the little I read, it shows that you have lost all respect from this woman. How did you get to this point? You've either done a very bad thing in the past that she can't forgive or you just married her without involving serious thinking...

Tell them the secret, your child, mental health and sanity are at stake, your wife and her family are being irrational, and inconsiderate, because should crisis occur, you will he held accountable.