She must be seeing a lawyer...what now?

[Awoken]

I have one area I could work on with W.

We have set up a schedule: M and W is supposed to be my night home with the kids. T and Th are supposed to her nights. We negotiate each weekend.

I've been staying away from the home on T/Th until late at night.
However, W has started coming home early on M and W, and interacting with us. I haven't said anything about it so far. I hardly want to interrupt her when she talking to the kids and say "ahem, it's MY night!", but that's how I feel.

This is a boundary I should set; how do I state it? how do I go about it?