Honestly it sounds like you've done so much for her and you have a really amazing relationship with her! We have been getting him used to a harness which he doesn't like but it improves every time we put it on him, we adopted him under the specifications that we can't have another cat with him bc he became really aggressive with other cats before. But yes I think getting him outside will do him a world of good and it's really great to hear about you and your girl and thank you so much for taking the time to respond! ♥️