I'm a horrible person

So, I have something I need to confess, and I know it is going to make me sound like a horrible person who is doomed to burn in hell. But it needs to be said, so that I can get my thought process in order. I kind of wish my dog would die. OK, so before you get out the torches and pitchforks, let me explain. My dog is not happy. As a matter of fact, I think he's probably miserable. But it isn't a medical thing. I can't just take him to the vet. I can't get him some pills or a shot and make it all better. First of all, he's old. He'll be 14 years old in September, and he's really starting to show his age this past year. His hearing seems pretty bad--where you used to walk into the house and have the dog already waiting for you, now you'll walk into the house and he's sleeping on the chair, and you can walk past him three or four times before he has any idea you're there. His eyesight is also poor. He's got cataracts in both eyes. If you look into his eyes, you'll see the milky white sheen inside the pupil instead of the dark black (or green, which he used to have when his eyes reflected light). I think because of the eyesight problem, he is much more cautious with his movements than he used to be. He really seems unsure about jumping up on or down from things. He'll stand at the top of the two little stairs to our back porch, just gauging his chances, sometimes until you push him out with your foot. Then he flings himself off the top stair, not sure where the landing zone is, rather than just stepping down onto the next step. He seems sort of lost or purposeless most of the time. He wanders through the house, randomly. He can't seem to settle in to one location for long. He wants to go out, but then barks to come back in after only a minute or so. He fusses to go into the bedroom (the door is closed to keep the boys out) but then immediately barks to come out when you close the door behind him. He just seems unsettled. I don't know if he just doesn't know where he is, or if he's uncomfortable and can't figure out how to make it better. He does have some loss of kidney function, but I don't know if that contributes to his desire to constantly go outside. When he goes out, he doesn't pee all the time or anything. Worst of all, the boys will get fixated on him, and they won't leave him alone. Ian likes to "flap" at him, and also grabs his collar and tags and pulls on him. When he catches Brendan's eye, Brendan tries to grab him. He'll grab hold of his back hips or his tail and won't let go. Maerlyn is surprisingly well behaved--he's never snapped at the boys or tried to bite them--but I know he can't stand them. He has always been the star of the household, the only child, and he doesn't grasp that he needs to move himself out of the way or remove himself from their zone in order to avoid their attentions. He's very stubborn: it's his house, so he shouldn't have to move. I just don't know what to do. He doesn't like other people--it truly did take years before Maerlyn ever allowed any of our family members other than us to pet him--so giving him to someone else is pretty much out. When he's with other people and we aren't there, even in our own house, he'll try to escape out of the house at the first opportunity. He somewhat enjoys spending time at my in-laws' home out in the country, but the same problem persists. If we aren't there, he sulks: he won't come inside, he tries to get out whenever possible, and he won't eat. My mother-in-law gets really worried about him. So that isn't really a good option either. And of course there's no way I could put him to sleep. There would have to be a really significant medical problem for me to even consider it, and right now he's reasonably healthy. Obviously I can't get rid of my kids either. So what do I do? I have no idea how to make the dog happier, and it makes me really sad to see him like this every day. So, that is why I said I kind of wish he would die. Yes, it's a horrible thing to say, and it makes me sound like a monster. But the dog simply isn't happy, and I'm afraid he never will be again. It's selfish of me to say, but it would be a relief. That doesn't mean I'm going to do something to end his life; like I said before, there is no way I would do that. But if he passed away from natural causes, I would cry and miss him terribly, but I would also feel better that he was finally in a happier place. Yeah, I'll probably burn in hell for even thinking that.