I was the same with my cat, i was dreading letting her out, but we rescued her as an unwanted kitten that had strayed at a very young age and she was very used to being outdoors constantly, so has always wanted to get back outside and explore - at least now shes in a much safer area with a nice warm bed to come home too. She doesnt go out for long periods and has learnt to tap at the door when she wants to come back in (we dont have a cat flap as its a rented house with glass doors), and fortunately she comes to being called if shes in hearing distance.

She does occasionally get a bit of a biff from local cats who think our garden is theirs, but in all honesty cats will do that and they make an awful racket because theyre just very vocal, usually the worst cats will do to other cats is lots of noise and a bit of flying fur! She came back in a bit shaken with a few tufty bits and i was worried but 5 minutes later she was fine, no lasting damage. Im much more worried about her getting run over or trapped in a garage etc.

I must say though, on a fundamental level i disagree with keeping moggies as 'indoor cats'. I do understand that pedigrees that are showed need to be kept in or in an outdoor run for various reasons, and also understand the worry of having a pedigree cat stolen, but cats are naturally inquisitive, adventurous, outdoor animals, and they need that fresh air and natural environment to explore and follow cat instincts in...even if they show no sign of wanting to go outside, its almost as if you're stopping them from ever being able to be..a cat! I dont think its cruel, i just think its unfair.