sh'e just doing what cats do.......they aren't like dogs at all. i have four and each one has a different personality. she's pissed because you took her wet food away. you could get her some wet food and mix it with the dry......that way she won't waste it.....wet cat food keeps in the fridge....have you thought about only giving her two TBS at a time? she doesn't need an entire can. that's a bit much for one cat..she's probably not mentally ill. just pissed. cats have a very strong independent streak and she's acting out. they are very, very intelligent. when i open my raisin bran cereal box, one of my cats runs into the kitchen and stands by HIS bowl for a little bit of milk....have hope, dear....your cat is probably just fine.....xoxo pat