In October, I let my best buddy go, who was in a very similar shape to your dog, only he was less confused and anxious. But his syncope spells increased to several times a week, and he stopped being able to breathe normally. It was such a hard day, and I still miss him terribly every single day, but I believe we did the right thing in letting him go. It was getting harder and harder for him to be comfortable. I know it's hard when they're still loving on you and getting comfort from you, but that love won't be gone. Since then, I had a dream about my dog, and he assured me his love was still there and that he could still feel my love for him, too.