If you followed her gaze you might be looking out a window at a tree, its branches waving in the breeze and the light. Or at her face (or your face, depending on where you are standing and the angle you are looking from) reflected in the black glass of the window at night. Or perhaps at a corner of the room. That dustball? That thread on the carpet? But nothing that you look at can tell you what she is seeing because she isn’t. She is only perplexed about herself.
One of some very short stories.