Why do u think Gene refused to hear the end of Leper's story and retreated abruptly from his vermont home??

Why Leper's talk disturbs Gene so much is not made clear at all; Gene doesn't say why he is so incredibly upset at it, though presumably it has something to do with him identifying with the feelings that Leper is expressing. Still, the prose in this section is rather murky, with the only reason that Gene gives for not wanting to hear it is that it has "nothing to do with [him]" (143). Does this mean that Gene feels responsible for what happened to Leper? On the other hand, how could he feel any responsibility, not having been there when Leper started going crazy, and after being a better friend to him than most of the boys at the school. Does Gene feel that he too is going crazy, which is why he doesn't want to hear it? Or is Gene simply being callous, and doesn't want to help Leper out any more? Because the motivation for Gene flipping out and running away is anything but clear, his reaction doesn't have the same power that the prose clearly intends it to have. Gene says that he "didn't want to hear any more of it. Not now or ever, ŠI didn't want to hear any more of it. Ever" (143); the repetition emphasizes his sentiments, but since it is hard to figure out why he is acting like this, it is impossible to empathize.