I’m so sorry for your loss.Robert Lee, I feel the same way about my Sheba. She died last Sat.
If I had taken her to the vet sooner, and to a different vet, then I think she'd still be with me. Coulda shoulda, woulda. We can beat ourselves up pretty badly in hindsight. But don't blame yourself, even though it's very painful things happen for a reason. Just know that you gave your fur baby a loving life and I'm sure he she was thankful to have you as their pet parent. Just remember all the good times that you had. That's what I try to do and I look at all the pictures and the videos that I took of Sheba. She was the love of my life and she knows that. God wanted her, he knew that I did the best I could for her and you have to realize that as well. You know when you're ready get another cat I'm 66 and I still plan on getting another cat. Not right away but I will eventually. God bless you!