That's terrible, Kathy.
I don't know what kind of terror...er...terrier you had, but I babysat 3 adorable Jack Russels (Parsons, or whatever they are calling them nowadays). A friend got 3 from the same litter-2 males and a female. One a show prospect. 3 months old. Good bloodlines/breeder. They had their own crates and schedules.(She only had them a few days and had an out-of-town emergency.)
First day-one ripped the females' leg. Second day-the one male ripped half the other males' face off. Third day-they dug a hole under the fence and went tearing down a busy highway. By the end of the week, I was in tears, and all three dogs were bloody and maimed. These were LITTLE PUPPIES. It was definately NOT play biting.And SO FAST! I have been around dogs all my life-from Wolves to Yorkies, trained Dobermans for show, had 2 grooming shops,worked for a Vet, and never seen anything like it. She found a home for the one male pup (pet-free) and that solve the problem. I don't care what people say about "No bad dogs-only bad owners." They are as individual as people, and I know some pretty rotten people that were raised right, too.
My friend felt she was doing something wrong, and felt horrible and guilty-don't feel that way. You gave it your best try.
There are too many nice animals that need a home.
-Stef*