My cat was depressed for over a year when my dogs passed away.
She use to sleep in the same room them & now she won't step foot in there.
She doesn't even care for the dogs we have now.
She's warming up to them but she doesn't interact with them like my other dogs.
My dogs literally raised her since we rescued her @ a very young age.
She basically acted like a dog, but in a cats body.
She's not been the same since.
Maybe it's age, but I fully believe she misses my dogs.