Dad was a farm boy. Once an animal reached the point where they were suffering and not really clear about things, Dad would have put her down. Probably wouldn't have given her medication beyond say, antibiotics or similar; but then he was hardly willing to care for himself beyond that. Before he had his first heart attack, he felt it was cruel to keep a sick old animal alive, since they couldn't really understand what was happening and they would never get well. And the expense was more properly spent on one's human family. I'm of the same mind (I'd never take my cat to the vet unless he was showing symptoms of something, but he gets the special food anyway, so it's moot).
[Now let me add that my BIL is an emergency vet, and from his inside view of the industry I feel about the same way toward vets as I do toward cosmetic dermatologists.]
At some point, Dad would point out that we were being selfish, forcing an animal to stay alive because we couldn't bear to part with it, or couldn't see how much it was suffering, and that the suffering wasn't going to end, or make sense, or help any of us. I remember him telling me, right before he died, that he wished he hadn't made it to the ambulance the last time. I knew why, he didn't have to explain it. Later he told my mom he felt he'd upset me by telling me that, but he didn't, not really. Knowing it's time, and accepting it, are two vastly different things, separated by an impenetrable wall of tears.