The betrayal could lead to Naruto having trust issues not only with Sakura but also with others in the future. He might become more guarded and less likely to open up to people. For Sakura, if she comes to her senses later, she would have to face the enormity of what she has done. She would have to grovel for Naruto's forgiveness, but it would be a long and difficult road to regain his trust.
It often changes drastically. Sakura may initially feel hurt and angry. She might start to question all her previous beliefs about Naruto. For example, if Naruto betrays her trust in a battle situation by seemingly siding with the enemy, Sakura's view of him as a reliable friend and teammate would be shattered.
Another plot could involve jealousy. If Sakura becomes jealous of Naruto's growing popularity and power among the villagers, she might betray him. She could spread false rumors about him, which would lead to the villagers turning against Naruto.
If Naruto gets hurt by Sakura, their relationship could become strained. Naruto might be confused and hurt, both physically and emotionally. He might start to avoid Sakura at first.
It would likely strain their relationship at first. Sakura would probably be very angry and hurt, both physically and emotionally. She might start to question Naruto's true nature and whether he really was the friend she thought he was.
It might also affect how their friends view their relationship. If Naruto snaps at Sakura in front of others, their friends might try to mediate or take sides. This could further complicate their relationship as they have to deal with not only their own feelings but also the opinions of their friends.
In the Naruto Sakura The Last Fanfic, their relationship could be explored in many ways. Maybe it shows them having deep conversations about their dreams and fears for the future. They could also be shown training together, with Naruto helping Sakura improve her physical combat skills and Sakura teaching Naruto some basic medical knowledge. This would not only strengthen their bond but also show how they are complementary to each other. Additionally, the fanfic might explore their relationship through their interactions with other characters. For instance, how they react when someone tries to come between them or when they have to work together to protect someone they both care about.
She may feel angry at first. Sakura is a strong - willed character. She might think that Naruto has made this decision without considering her feelings. In the fanfic, she could go on a rant about how he should have talked to her before making such a big decision.
Naruto could initially be angry. He might think Sakura overreacted. But then, after a moment, he would probably realize his own mistake if there was one. He'd then try to play it off with a joke to ease the tension between them, like he always does in tough situations.
Naruto could also feel a deep sense of hurt. After all, he has been through a lot with Sakura. In the face of her betrayal, he might start to question his own judgment of people. However, being Naruto, he would not give up easily. He might try to find a way to redeem Sakura or at least make her see the error of her ways. He would draw on his own experiences of being ostracized in the past and use that to try to understand her actions and find a solution.
The relationship would become very tense. Naruto would likely avoid Sakura and Sasuke. There would be no more of the friendly banter or the complex emotional triangle that was there before. It's a complete shift from their normal relationships in the original story.