I nursed him back to health and raised him to be a big strong cat.
You must have really cared for that cat.
I'm a cat lover and after I found the kitten alone and abandoned, I took it under my wing and we had a strong bond.
This is great to do. Caring for sick and injured animals is what you should be doing.
But now I think I want a different cat. This one isn't as interesting as he used to be.
I am sorry that you feel that way about the cat you had for so long and took care of. You can always adopt another cat that needs a home and then you will have two.