...I wonder...whoever was writing all the notes says they feel "unsafe" with Elise and MJ working together, and that they think Elise is a punk.

The last piece of the puzzle is who the notes belong to. I'd say it was the second woman in the photograph - "me", except...hm. For that one note that talks about Alice not wanting for an anniversary. I'm not sure if that's supposed to be a romantic anniversary, or some other kind. Since Alice seems pretty cozy with MJ in the other photo.