Perhaps Naruto's friends are going through their own personal issues. They could be so focused on their own problems, like family troubles or struggles with their ninja training, that they unconsciously start to ignore Naruto. They might not even realize how much they are hurting him by their lack of attention.
One possible reason could be jealousy. Maybe Naruto has been getting more attention from the village elders or teachers because of his potential. His friends, feeling left out or overshadowed, might start to ignore him out of envy.
It could be a misunderstanding. For instance, Naruto might have been wrongly accused of something, and his friends, without fully investigating, start to distance themselves from him. They might believe the rumors and false accusations, leading to them ignoring Naruto.
One reason could be a misunderstanding. Maybe Harry said or did something that his friends misinterpreted. For example, if he was overheard making a comment that seemed critical of them but was actually taken out of context.
One possible reason could be that Kakashi is preoccupied with other important matters in the village. Maybe he has some top - secret missions or tasks assigned by the Hokage that demand his full attention, leaving him with little time to focus on Naruto.
One possible reason could be that Naruto is afraid of endangering his friends. He has many powerful enemies, and he might think that by staying away from his friends, they won't be targeted. For example, Orochimaru was always after Sasuke, and Naruto might fear that his closeness to Sasuke could put Sasuke in more danger.
Naruto might initially feel sad and confused. He could try to prove himself to his friends by working hard on his ninja skills. For example, he might train extra hours to show his friends that he is worthy of their attention.
One reason could be jealousy. Maybe Harry has achieved something great like getting a special magical power or a high honor in their magical world, and his friends feel envious. Another reason might be a misunderstanding. For example, Harry could have been wrongly accused of something, and his friends believe the false rumors without giving him a chance to explain.
One possible reason could be jealousy. If Naruto becomes too powerful too quickly, his friends might feel overshadowed and abandon him out of envy.
One possible reason could be envy. If Naruto suddenly gains a great deal of power or attention in the fanfiction, his friends might feel left out or jealous. Another reason could be a misunderstanding. Maybe Naruto is framed for something he didn't do, and his friends believe the false accusations without giving him a chance to explain. Also, in some fanfiction, a change in Naruto's personality, like becoming overly aggressive or secretive, could lead to his friends growing to dislike him.
One reason could be to seek greater power. In fanfiction, the world outside Konoha might be seen as having more opportunities for growth. They might want to train with different masters or learn unique jutsu not available in Konoha.
One possible reason could be jealousy. Maybe Naruto has achieved something great and his friends are envious. Another reason might be a misunderstanding. There could have been some false rumors or misinterpretations of Naruto's actions that led his friends to believe he wasn't trustworthy or a good friend.
There could also be friends who are so loyal to Naruto that they would consider following his request if they truly believe it's for the greater good. However, they would be deeply pained by it. Kakashi, for instance, might understand Naruto's selfless nature but would also struggle with the moral and emotional implications of taking his life.