Savannah came to us as an OAP. We knew her chances of being adopted were very low. So we all felt very sad for her. She acted very elderly, and she was obviously in some pain, but had a lovely temperament.
We eventually took her to the vet, and she was diagnosed with late stage cancer. Having her put to sleep was a very difficult decision to make. I was fortunate I didn't have the last word on it.
Sometimes this work is just brutal. Well, really, often times.