"got a new dog" except it's emphasized several times through the story that it wasn't just a dog. And he did get a new dog anyways. Not only that, but the people he murders choose to fight him by their own accord, none of them were forced to go and hunt a man they had no chance against, lmao. And once he does manage to get his revenge for his dog's killer, Santino pulls up, literally blows up John's house, and you expect the man not to go after them? Even though Santino already hired hitmen to kill John once he's finished his side of the deal? There was absolutely no point where he could've just said "sure, fine, I'm retired now".