Im sorry about this sad news. You need to do what is best for Casey. I know when my family picked up Primo, a collie mix, we thought he was the right dog for us. We were all acting on impulse and had to bring him to the shelter. I still feel terrible about it, and it's been over a year it happened. Our yard was too small for him and the "breeder" lied to us about everything. She said he was 4 months old. Impossible. He held his pee all night, was already obediant and was already huge. He also had a huge scar on his back that the "breeder" told us would heal naturally. I'm sure he was adopted, as he was a beauty and a very sweet dog, but I still can't forgive myself.

A bit off-topic, sorry. What I was trying to say was that we couldn't keep him because he was too big a dog for us. I didn't want to make him miserable. Same thing with Casey. You need to do what's best for him. I can't even imagine the pain you must be going through but I do know that by doing this for Casey, it'll be what's best for him.

As been mentionned, maybe you can see Casey on occasional visits. Good luck.