She wants him to kick not just his wife but his child out of his life for her????
Toxic is very much the right word. I'm glad she's out of your home and you have more peace, but I'm so sorry this is still going on at all. I would hope that any parent would have enough respect for their children to not have anything to do with anyone whose goal it is to break their bond with their children. Just so not OK... it should have been over, permanently, right then. Even if she doesn't still claim that as a desire, the selfishness it demonstrates is beyond unacceptable.
Me, 30ish bi female, been doing solo poly for roughly 5 years. Gia, Clay, and Pike, my partners. Davis, ex/friend/"it's complicated." Eric, Gia's husband. Bee, Gia and Eric's toddler.