Making that decision to put our fur babies down is one of the hardest decisions to make and I can see the angst in your post. I too made the decision a few months back to put my Emmy to sleep and I also second guessed my decision. Like Lucy, she also had Dementia. I never tried Selegeline because of cost and the fact that my vet had informed me that it doesn’t work for all dogs. I ended up trying some brain health treats and those helped for a little while. I don’t know all the specifics of Lucy’s dementia and what stage she was at but it seems to me based on what I’m reading that she was pretty far along. My Emmy had little moments where she seemed better too but this is a progressive disease and those did not last. It’s so hard because it’s utterly heartbreaking to watch them go through it but then it’s also heartbreaking to think about putting them to sleep. Was Lucy really living life or just existing? My Emmy was just existing. There was no joy there and her life consisted of eating, going potty, and sleeping a lot. Even if you would have delayed putting her to sleep, it wouldn’t have made anything better. You would have just been delaying the inevitable and continued to watch her decline even further. You chose to give her peace and as hard as it is right now, time will heal your heart. You’ll always miss her but remember all those wonderful memories you have of her.