My cat, Zeppelin... has been living with me for 7 years. We have lived at this residence for 3 years. Just over the last few nights, she has become afraid of her own reflection! She growls at the T.V. or the glass in the entertainment system, her reflection in the hallway mirror makes her HISS and growl and run... she is acting crazy! Nothing has changed over the last few days. She still lives in the same place, the same furniture is in the same place, and I have not introduced any new pets or roomies... what the heck??

My thought is that most likely there is an outside cat that has upset her, so she is thinking that the cat in the reflections is that cat.