In some fanfictions, Naruto might become unstable if he discovers some dark secrets about his past, such as his father's actions having more negative consequences than he thought. It could also be due to the influence of a powerful and malevolent enemy who has the ability to mess with his mind, like using genjutsu continuously to make him doubt his reality and purpose.
Well, sometimes in fanfiction, the author might make Naruto unstable because of a broken bond. Maybe his relationship with the village turns sour. He's always been about protecting the village and if they suddenly turn on him, like if they wrongly accuse him of a crime he didn't commit, it could shatter his mental stability. Also, if he has to bear too much power too quickly, like getting the power of all the tailed beasts at once without proper preparation, it could overwhelm him and make him unstable.
In some fanfictions, Naruto might be depicted as mentally unstable for various reasons. One could be the extreme stress he endures. He has lost many people in his life, like his parents at a young age. This could potentially lead to psychological trauma that some fanfic authors might explore and exaggerate, making him seem mentally unstable.
Perhaps a dark power corrupts him. In the fanfiction, there could be some sort of dark chakra or evil entity that latches onto Naruto. This entity could slowly eat away at his emotions, starting with his heart, making him gradually lose his ability to feel empathy and turn heartless.
One possible reason could be the extreme pressure he faces in the fanfic. Maybe he has to deal with much more powerful enemies alone, which overwhelms his mental state. Also, if he experiences a lot of betrayals in the fanfic, like friends turning against him, it could lead to his mental instability.
Maybe Naruto discovers that the village he has been trying so hard to protect has been using him all along. He might find out some dark secrets about the Hidden Leaf, like they were involved in something immoral and were just using his power, which would shatter his idealistic view of the village and leave him heartbroken.
It could be the influence of a powerful enemy or a dark power. Suppose there is an enemy who has the ability to manipulate emotions or a dark power that corrupts Naruto's mind. This could lead him to change his personality and become more like Gaara. For example, if the enemy makes Naruto feel alone and unloved, he may start to develop the same cold and distant behavior that Gaara once had.
One possible reason could be extreme loneliness. Naruto has always faced some degree of isolation in the original story. In a fanfiction, this could be exaggerated to the point where he feels there's no way out and becomes suicidal. Another reason might be the failure to protect his loved ones. If in the fanfiction, he fails to save his friends or the village multiple times, the guilt could be overwhelming.
In such a fanfic, it might be due to a false accusation. Suppose Naruto is wrongly accused of a heinous crime like mass murder in the village. Everyone turns against him, and he has no way to prove his innocence. This overwhelming sense of injustice and isolation could drive him to suicidal thoughts. Also, if he discovers some dark secrets about his past, such as his parents' real cause of death being related to some sort of betrayal he unknowingly caused, it could break his spirit.
One possible reason could be a major betrayal he experienced. Maybe someone he trusted deeply, like a close friend or a mentor, turned against him. This would make him more guarded and distant to avoid getting hurt again.
One possible reason could be a major betrayal. Maybe someone he trusted deeply, like a close friend or a mentor, turned against him. This would make him lose faith in people and become cold as a form of self - protection.
One possible reason could be a great betrayal. Maybe he discovers that someone he deeply trusted, like a close friend or a respected mentor, has been using him all along. This would shatter his trust and make him withdraw from people, thus becoming cold.