One possible reason could be a misunderstanding. Maybe Hinata is misinformed about Naruto's actions or intentions. For example, she might be led to believe that Naruto has done something harmful to the village when in fact he's innocent.
One possible reason could be political intrigue within Konoha. Maybe there are certain factions that see Naruto and Hinata as threats to their power. For example, they might be afraid of Naruto's influence due to his status as a hero and Hinata's connection to the Hyuga clan. Another reason could be a misunderstanding. Perhaps some false information is spread about them that makes Konoha turn against them.
One possible reason could be a huge misunderstanding. Maybe he thought Hinata did something really bad to his friends, like unknowingly leading the enemy to them. Without knowing the truth, his hot - headed nature made him lash out.
Well, one reason could be that Hinata's extreme love for Naruto gets out of hand. In the original series, she's very shy but deeply in love. In a fanfiction, this love could transform into an obsessive - like stalking behavior if the writer wants to explore a darker side of her character.
It could be due to a power imbalance. If Naruto's power as Hokage makes her feel overshadowed or unimportant, she might be led to betray him. Also, perhaps she discovers some long - hidden secret about Naruto that she can't forgive, like a connection to a past enemy or some dark side of his shinobi past that he has kept from her.
It could be due to miscommunication. Suppose there was a misunderstanding between her and Naruto. For example, Naruto might have said something that Hinata misinterpreted as him losing interest in their relationship. This confusion could have led her to seek comfort in another person, which unfortunately led to cheating.
One possible reason could be that Naruto has a dangerous mission that only he can undertake. The safety of the village or the greater good might demand his immediate departure, even though it's hard for him to leave Hinata in such a state.
One possible reason could be a misunderstanding. Maybe some false information is spread about Hinata that makes Naruto believe she has done something unforgivable. For example, if there's a plot to frame her for treason against the village. Another reason might be for her own safety. Naruto might think that banishing her would keep her away from a greater danger that is targeting her because of her relation to him.
Jealousy could also play a part. Naruto becomes very powerful over time. Some of his peers or even superiors in the village might be jealous of his growth and popularity. They could spread lies and manipulate others into believing that Naruto is a threat. This would gradually turn the whole village against him. For example, a less - known ninja who feels overshadowed by Naruto's achievements might start the ball rolling on the betrayal.
One reason could be envy. Maybe Naruto sees Hinata as having something he doesn't, like a more stable family situation, and he lashes out in jealousy. Another reason might be that he's just being a typical, rambunctious kid who doesn't realize the impact of his words or actions on Hinata.
In some fanfictions, external forces might be the cause. Perhaps a powerful enemy threatens Hinata and tells her that staying with Naruto will put him in danger. So, to protect Naruto, she decides to abandon him. This adds a tragic and self - sacrificing element to the story.