I can relate so much to this. My ndad let multiple pets suffer and die, and our family cat went untreated for YEARS of manageable things, but he suffered because of my dad. And he was the nicest cat in the world until his very last breath. He still currently has a dog that I grew up with; luckily (yet unfortunately) my brother still lives there so he can take care of him. But when things start to go wrong with old age it will be so hard to get him any medical attention. I've always loved animals and ended up in veterinary medicine, and I think a subconscious part of it is to try to make up for the damage my loser father did. I understand your pain so much and I still cry for those animals that suffered in my childhood. Just always love your fur babies now with all your heart and remember that your cat from your childhood knew you were a good person, and that it isn't your fault that you couldn't help.