How long have you had Calle?(I lose track of time ). It can take weeks if not months, in certain cases. Some people jump to the conclusion WAY too early that there cat will not adjust. Of course she will hiss and growl!!! My Sterling HATED every cat that came in after him. Growling for weeks with mistrust, but he always came around to befriend the newcomer. Even my shiest cat Fern, who I also believe might be happier without all the other cats, manages to coexist with them. She'll keep her distance from them but plays and asks for human attention when she wants it. So I do not feel her life is bad. Biddy and Mote fought when Biddy first got here. They were working out the "who's boss" issue, and they are fine with each other now. (just squabbles)

I Know that people will say that certain cats MUST be only cats, All I am saying is don't RUSH into anything. Give it TIME TIME TIME!!