The most straightforward resolution could be Hinata explaining the truth to Naruto. Once he knows the real situation behind her 'betrayal', he realizes he was wrong to hate her and they reconcile.
In this fanfiction, Hinata's betrayal might be painted as her leaving Naruto's side when he needed her most. However, there could be a deeper reason. Perhaps she was under a genjutsu or some kind of mind control. Naruto, not knowing this, simply hates her for what seems like abandonment, but it's all a big misunderstanding.
Some people create such fanfiction maybe because they like to explore alternative or dark storylines. They might think it's interesting to deviate from the canon relationship between Naruto and Hinata.
In fanfiction, the evidence often lies in the way the author portrays Naruto's interactions. For example, Naruto may be shown being cold or dismissive towards Sakura, like avoiding her company or not showing any romantic interest. Meanwhile, with Hinata, he could be depicted as being more affectionate, like blushing around her or always coming to her aid. But it's important to note that this is all in the realm of fan - created interpretations and not the official canon.
One possible reason could be for the sake of creating a more complex love triangle in fanfiction. Maybe the writer wants to explore a different dynamic where Naruto and Hinata's relationship is strengthened by having a common dislike for Sakura. It could also be that the fanfiction writer is trying to give Hinata more agency and make her a stronger character by having her oppose Sakura in some way, perhaps in matters related to Naruto's affections.
A possible theme is rivalry. The fanfiction might portray Hinata as a rival to Naruto in some aspect, causing his hatred. For example, in a political or power - struggle context within the Naruto universe.
Maybe the fanfiction portrays Hinata in a way that doesn't align with her true character. For example, it might make her overly aggressive or weak in a way that doesn't fit the original concept.
Some fans who like Hinata might be turned off by such fanfiction and avoid it, which could lead to a division in the community. Those who enjoy the fanfiction might continue to create and share it, while those who don't might start to distance themselves from that part of the fandom.
In some fanfics, the idea of Naruto hating Hinata might be a plot device to create drama. Maybe the writer wants to explore a different kind of relationship dynamic than the canon one. It could also be that the writer has a unique interpretation of the characters' personalities and how they might clash in certain situations.
Some fans might be divided. Those who like Hinata might support the idea in the fanfiction if they feel it gives Hinata more depth or a more interesting storyline. On the other hand, fans of Sakura might be offended.