Hello HelloWorld. I offer you my condolences on the loss of your dog Lily. I understand completely how you feel. I had a dog I loved dearly. Her name was Ginger. Ginger lived to be 16 years old. In her old age she developed a chronic cough and severe arthritis in her hips. I had her on all sorts of medication but after a while it didn't help. I had to make the heartwrenching decision to have her put to sleep. I hated to lose her but I hated worse for her to suffer.
I know you loved your dog. It sounds like you took such good care of her. Do not feel guilty. Vet bills are high and it is possible they could not have fixed her itch.
You will always have the happy memories of going camping with her. My heart is with you.
