MC as a woman , I just cannot understand where your W head is at. I don't think many woman could walk away from their kids like that. I certainly don't know any.

That would lead me to think that her actions may not be her fault. Do you think there is a mental disorder happening. Have you discussed whats going on with family doctor. Mental disability is exactly that, a disability. Woman have hormones and post natal stuff that happens and maybe she never really found balance after your last child.

Might be grasping at straws but her behaviour would suggest a problem. Just a thought