Kirsten I feel for you. I understand that guilt because I have gone through this too. Our feral kittens (1 year old now) were born and raised outside. When I brought them in I said that I would never let them out again and I haven't. My husband and I have had several disagreements over this. He thinks I'm being mean and unfair to them. He says that it is in their nature to outside for play and fresh air. I refused to do it but I did feel guilty.
NOT ANYMORE!! After my experience in the shelter and seeing what those cats go through in such tiny confined cages my guilt when straight away!!
By going outside they run the risk of being hit by cars, hurt by loose dogs, poisoned, or possibly getting some illness from a stray. Not to mention what could happen if some mean people got them!!
I have decided that if the worst thing that happens to them in their life is being confined to the entire house, warm in the winter, cool in the summer, fresh water and food at all times, and any medical care they need, groomed, cleaned up after, and loved to pieces then they are just going to have to deal with it!!!!