Wow, this just took an incredibly depressing turn. That Erin's hallucinations because of her brain damage has caused an insanely large rift between her room mate and her friend, the one who caused the brain damage in the first place. That Elliot is less mad, but rather just pities Erin for acting to her hallucination's demands and just asks her to just grow up. Meanwhile, Erin is still convinced she's not crazy to the point of launching an X-Box 360 (which to a game reviewer must be pretty valuable) at her room-mate who calls her crazy's head (not at her, but directly at her face, which is slightly different in feelings of malice).
At this point, I wouldn't be surprised if the rift and her proclamation of not being crazy despite everyone yelling at her that she is and she should take the meds which make her feel like a half-vegetable state will cause her to go into a deep depression. God damn it Grey, just god damn it.