My cat has stopped eating

Question
My cat is a mixed breed long hair 7 year old female.  Typically she comes in the house very little but she hasn't gone outside since Thursday (today is Tuesday).  She is very thin and will not eat anything.  She has been drinking water and had been eating a couple of bites of food or tuna a day until today.  Typically she eats regular cat food and whatever she may catch outside.  There does not appear to be anything wrong with her other than these two symptoms (not eating and staying inside).  My 18 year old moved out of the house about three weeks ago and we thought maybe she was depressed, but this has gone way too long and extreme to be depression.  Do you have any ideas, thoughts or suggestions on this please?
Thank you,
Deborah Murray

Answer
Deborah,

Get your cat to the vet!!!!!  Cats are too smart to starve themselves unless there is a problem!!!!!  The fact that the cat is not eating and thin and drinking copious amounts of water is symptom enough for an immediate trip to the vet.

Best regards... Norm.