Thank you for the added information. It helps a lot. I believe I can now be of help with this issue. Once we are in question/answer mode, the site doesn't have a mechanism for switching to chat mode. So let's continue this way.
First, let me say I can imagine how confusing and distressing this situation must be for you. Distressing can be understood--your son is very distressed. But why do I say confusing?
Because his grief seems to be stretching on in time and in intensity above and beyond the normal bounds of a teenage boy's expression of immediate grief for the loss of his beloved dog. And this is actually the key to my answer to you that you need to consider and think about.
Your son's behavior is not normal. The other kids' behavior is much more within normal bounds. I sense you know this within yourself. This is why I asked about possible Asperger Disorder. Your responses seem to indicate there may be a mild form of AS or some features of AS. Or perhaps some other slight developmental disorder. Because his relating to the world and events of the world seem just a bit off in a developmental way.
Therefore, there are two recommendations. If he continues to exhibit these same behaviors unabated or they become even more pronounced, then you know you have to seek professional interventions. You would then need to find a psychologist who has experience with kids who might have AS. That would be helpful so there could be an evaluation as well. And even if ruled out, the techniques of working with AS kids will be useful for your son.
Before that, though, I would recommend you take the unilateral action of getting another dog given that you are willing. You need to announce to him that you are going to do that. So only make the announcement when you are ready to get the new dog. Invite him to come with you or not as he wishes. Let him know it's his choice to come or not. Encourage him to come even if he says he doesn't want to. Tell him you would like his opinion on the new dog, which new dog would be good to choose. Then get the new dog and see if he is able to bond with it. That will give you good information about your son's condition.
Hopefully your son will bond with the dog within a few days and this will end the episode. I wish you the very best!
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