What a beautiful cat, in the photo of your opening post!
I love cats, and I've owned several and unfortunately seen them die. They usually live around 15 or 16 years. Only one died prematurely of feline leukemia at around 10 years of age.
One was my neighbor's cat, but I gave him a lot more attention than my neighbors did, so he behaved like he was my kitty, and would run up to my car when I came home from work. I'd pet him on the sidewalk when I got home for around 30 minutes every day.
My neighbor (John) told me the little guy had some condition, and the vet told him his cat would only live another 6 months or so. And while he was thin, he seemed happy, and was most certainly loved. And lived another 7 years! He only died because he got in a fight with some other animal, was badly injured and died of some infection, despite being taken to the vet after and pumped full of antibiotics.
So... you never know.
I hope Buddy has more life and years in him than he seems to. And that you both can enjoy the time you have with him.