Who is this woman & what has she done with my wife

[THX-1138]

I will see my W this afternoon at D14's soccer game.

I know that W is having a PA, but she does not know that I am aware of it. She filed for D several weeks ago, and I am going insane with the knowledge of the OM, and of the D filing.

I have been dark for about a month now. She came to the house last week (to drop of some clothes for D14) and we talked for a few minutes. Civil and friendly.

New Questions:

When I see her at the Soccer game today, how should I act?
I know that I am supposed to be friendly and have PMA when I see W. I think that I can actually pull it off. Should I sit with her? Should I talk with her about neutral stuff? She really wants to be me my friend already. Is that cake eating?