I thought that my cat was depressed because he slept all day ignoring me; so I got another cat to keep him company and now I have 2 cats that sleep all day and ignore me. Lol
Do your cats get along? I imagine mine would hate another cat being in the house.
He sleeps on his own during the day, most of the time. But if I'm doing something important he seems to pick up on it and the curiosity kicks in. When darkness falls however, I must sit on the sofa for lap snoozing, lest I be shrieked at incessently.