One possible reason could be that in the fanfiction, his family might have been portrayed as overly strict or controlling. Maybe they forced him into a certain path he didn't want to take, like a particular ninja training regime that Naruto found too rigid.
It could also be due to some external influence. Perhaps an enemy manipulated Naruto's mind in the fanfiction, making him see his family in a negative light. This enemy might have used some form of mind - control or false memories to turn Naruto against his family.
One possible reason could be a misunderstanding. Maybe there was some miscommunication in the past that led Naruto to believe his family didn't understand him. For example, if his family had different expectations for his future as a ninja compared to his own dreams.
Another reason might be that Naruto has been influenced by external forces. Maybe he has made some bad friends or been involved in some situations that made him think being cold to his family was the right thing. He could have been brainwashed into believing that his family was holding him back from achieving something greater.
One possible reason could be a misdirection in his goals. If in the fanfiction he is overly focused on proving himself to the village, he might think that family is a distraction. So, he starts to distance himself from his family to concentrate more on getting recognition from the village.
One possible reason could be a divergence in values. Maybe in this fanfiction, Naruto's family holds values that are completely opposite to what Naruto believes in. For example, if his family is shown to be more focused on power and status within the Justice League world, while Naruto values friendship and helping the weak.
One possible reason could be that the fanfiction portrays his family in a way that goes against his ideals. For example, if his family is depicted as being involved in immoral or unethical activities, Naruto, with his strong sense of justice, would have a hard time accepting them.
It could be due to miscommunication. In the fanfiction, perhaps there were misunderstandings within the family. For example, Naruto might have overheard something that made him think his family didn't have his best interests at heart, but in reality, it was all a big mix - up. So, he gradually lost trust in them.
One possible reason could be a feeling of betrayal. Maybe he found out some long - hidden family secrets that made him lose trust in his family. For example, if he discovered that his parents had made a deal with some dark force in the past that had negative consequences for him or the village.
One possible reason could be that he has faced a lot of misunderstandings within the family. Maybe his family has certain expectations that he can't meet, and over time, this has led to his coldness. For example, if his family doesn't understand his dreams or ambitions, Naruto might feel alienated.
One possible reason could be a long - held misunderstanding. Maybe Naruto discovers some family secrets that he misinterprets as betrayal or neglect. For example, if he finds out that his family had made some sort of pact that he disagrees with, it could lead to his rejection.