When in discussion about child custody, bring up the fact that she's trying to take an infant cross country to live in the house of a man she met over x-box live. It may not be a great standing argument, but piling it ontop of the fact that you did much of the raising will hold more ground than her simple argument of being the biological parent. I'm very sorry to hear this has happened and I can only say that you must be certain to get good counsel.
I also agree with filing the abandonment while she's gone, it will provide documentation that points toward her general disregard for the child.
Best of luck to you man, you have the support of this forum.
“This body is not me. I am not caught in this body.
I am life without limit.”