I would not let her come over to put the kids to bed. I know that is a rotten thing to say but again, she is doing that to fill a void. She is ultimately making the decisions that will change the dynamic of the family, not you.
I had a stern conversation with my L. I told him I was not made out of money and if I felt like he was not being very effecient with his time, I would find someone else. The more you and your W can figure things out on your own, the less time the L will have to spend.