Crazy, in fact probably totally insane.
Acting in the manner of Tom Cruise jumping on Oprah's sofa or Joaquin Phoenix on the Letterman show.
Hearing voices and imagining things that haven't happened or people saying things that they haven't.
Possibly caused by some recent trauma, however more than likely always present just brought to the surface in times of high emotion.
Person 2: "She's been totally Guano Loco since her boyfriend moved to Greece and dumped her ass"