Back in 2011 our half-Sheltie, Boo-Boo, developed a large tumor on his spleen. After consulting with the vet, who advised us that he might not survive an operation, we resolved on taking him home and making him as comfortable as we could. After one episode in which we were sure we were going to lose him, my wife patiently nursed him back to health, and he lived an entire year virtually symptom-free, and got to enjoy all the love and affection we could give him. Last Thanksgiving it finally caught up to him, and after a very brief episode of collapse he laid down in his little bed and died. I'm glad now that my wife refused to give up on him. And our new little Sheltie, Dickens, is the virtual reincarnation of the guy.
The only hard part about taking little doggies into your life is the knowledge that you will probably outlive them. But it's still worth it, and then some!