We had a dog- more human than dog- that due to violent abuse became crippled fairly early. We did see the worrisome warning signs early but even a superb vet didn't recognize the extent until it was obvious as she was so happy and so smart (she would look back and correct her own foot at the start). Dogs do not usually show chronic pain the way we do. When they are so loved and included in everything they fight as hard as humans. We paid through the teeth for meds which weren't even that effective, we made a wheelchair she used everywhere including camping and the beach, she had 2 more fantastic years. Her only real visible distress came from separating her for one night (she cried for 2 days and we got enough meds to sedate her before putting her down until I realized it was only because we hadn't carried her upstairs on a dog bed to my sister- and the meds didn't work to sedate her for even a dog twice her size, which we weren't at all surprised). But in about 5 months, she could not right her body if she fell to the side while laying down, and that made her afraid and that we could not live with the fear of her experiencing. Even then it took the vet (a different one) 3 hours to put her down, a disgrace which is another story.
Everyone is different. If we had a house fire I'm saving the dog if I can. Period and regardless of risk. But I've still had to put down 6 over the years, and 3 we lost due to even worse situations. Whereas I rarely can cry for the loss of people, I (we all) cried for days nonstop for them.
The point is all we can do is love them and provide for them to the best of our ability. Nothing and no one will replace her. But we needed her as much as she needed us from the start. I am so sorry for all for the losses and fears of everyone here for their animals. They are FAMILY and called Beloved for a reason.
And tbh, I no longer care if people 'get that' or not. If they don't they likely have family, or haven't yet loved or been loved by any one or anything to that degree yet.