She doesn't get to opt out of parenting with you, unless you are like, um, a convicted felon or something.
Do you all not have lawyers? Are these negotiations passing through lawyers?
I can't believe a lawyer is telling her she can do this.
What about mediation? Most courts now order the parties to go through mediation first, especially when there are children.
I'm not sure I understand this process you all are in...
But I will say, get your emotional reaction to what she's done out of it. Don't let that drive what you do next. Her assessment of you as a parent and what rights she thinks you have aren't relevant; it's what she can prove and what the law provides for in the face of that proof.
You are still caught up in reacting to her; instead your focus needs to be on financial and parenting arrangements that are in their best interests and consistent with the parameters of local law.
"Go where your best prayers take you." -- Frederick Buechner