Awww that is so sad... R.i.P. Rusty, play happily at the bridge
It seems to me you did EVERYTHING you could to try and help Rusty. It was not your fault that this happened. You gave him much needed love and support during his last weeks of life, i think that is a very good thing. I think he probably left this life much happier than he would have been had you never adopted him & he had died in a shelter. You gave him a loving home for a few weeks, but at least he had a loving home, he deserved it.
Please dont let this experience discourage you from adopting another cat. There are many more cats that need love
Im sure you can find another kitty to be your companion over the years to come
It seems to me you did EVERYTHING you could to try and help Rusty. It was not your fault that this happened. You gave him much needed love and support during his last weeks of life, i think that is a very good thing. I think he probably left this life much happier than he would have been had you never adopted him & he had died in a shelter. You gave him a loving home for a few weeks, but at least he had a loving home, he deserved it.
Please dont let this experience discourage you from adopting another cat. There are many more cats that need love