Animals come in and out of our lives starting as kids. It never gets easy. I agree with Halifax on quality of life is an issue, but unfortunately sometimes the financial side is an issue that cant be ignored. Only you can make this decision. We had to give our cat KC the insulin shots. We did it while he was eating or right afterwards. Didn't seem to bother him too much at that time. Finally his time came and he died in our arms at the vets, before she could administer the kill shot. I'm a grown man and I sobbed like a baby. Pets, damm them, Lol