I am sorry for what you have to go through.
I too have a story to tell, its about a dog not a cat but the pain is the same.
When I was 5 years old my parents decided I needed a dog. The got me a beautiful golden reriever puppy. I still remember it like yesterday. IT was Easter morning and instead of waking up to a stuffed bunny and candy in a basket I woke up to a wet nose in my face. I made my parents let me take him to church with us that day and then to the egg hunt. He and I spent more time just playing than finding eggs. Later that night I was reading a book, and the dog in the book was named Duke so thats what I named him. I told him everyday how much I loved hima dn no matter what he would never be alone. From then day on we were inseprable. We lived close enough to school that my mom would walk me everyday, he would come with us. As I got older she would just let him walk with me to school. Somehow he knew to just go home and wait for the time for when I got out of school. At the end of everyday he was there waiting to walk home with e. Some days we would just run the whole way home other days we would stop and pick flowers and I would make him daisy necklases. He alwasys loved to have them on and would look so proud when I was done dressing him up. The greatest parts of my days were waking up to him and getting home from school, just to play with him. IT stayed that way right up untill the end. Even once I got to high school, instead of going out with friends after school I would rush home just to play with him. Not a night went by when he wasn't in my bed sleeping with me. Then shrtly after my 16th birthday I came home from school. My mom sat me down and told me she had to take Duke to the vet that morning. It was not good, it turned out he had a brain tumor and he most likely would not make it through the night so she should put him douwn. She remembered my promice to him and told the vet if that were the case she would bring him home to be with me, if he were still alive in the morning we would bring him in together. I was blown away, I had never noticed he was sick. My mom told me yes, when I was not around it was clearly visable to everyone but when I was with him he found the srtength to still play and act like a puppy. I spent that last night with him awake and just talked to him. He found the strength on last tiime at about 5 am to go for a walk with me through the woods, our child hood playground. A few hours later we took him in. I stayed with him like I promiced holding him the whole time. I remeber the last look he gave me, it said I love you , thank you for all he memories. I will see you someday again. And then he was gone.
I am 30 now and for some reason I still can not find it in my heart to have anouther dog. Just typing that out made me start crying. I still miss him terrably and am counting the days till see him again. I kept his tags and still pull them out a few times a year just to remeber the times I had with him. His ashes were scatered i our favorite wildflower spot, the very spot wher we would have picnics and make flower necklases.
I can tell you this though, the pain may never fully goaway but it does get easier. You will never forget the memories of all the good and bad times you shared. Just know that Kipper knows you are doing it out of love and its that love that tells you it right. Just be there to help litle Kipper though the last journey of life. Then lock all the memories you can in your brain, you can pull them out at any time and laugh or cry but just keep them.
Hugs to you and Kipper on this last great journy.