Naruto might initially be in shock. He has always idolized his mother, so if she suddenly hurts him, he would be completely taken aback. He might freeze for a moment, unable to believe what is happening.
If Kushina continues to hurt him, Naruto might have to defend himself while still trying not to harm her. He could use his skills to dodge her attacks and try to find a way to break whatever is causing her to act this way. He would be conflicted between protecting himself and not wanting to hurt the mother he loves so much.
Naruto would probably be very confused at first. Kushina is his mother, so her hurting him would go against his understanding of their relationship. He might initially try to talk to her, to find out what's wrong and if there's a way to fix it.
Maybe she's been possessed. In some fanfictions, characters can be taken over by dark forces. So Kushina could be under the control of some evil entity and that's why she hurts Naruto.
Kushina would be extremely worried. She would rush to Naruto's side immediately and start using her medical knowledge or any available resources to help him get better.
Naruto might be extremely heartbroken. He has always looked up to his mother, and being disowned by her would be a huge blow. He could become withdrawn and start to question his own worth.
At first, Naruto would be shocked and confused. His world view would be shattered. But then, he would draw on his inner strength. He has overcome so many hardships before. He might feel a deep sadness, but also a sense of resolve. He would still believe in the power of love and friendship, and use that to face Kushina's betrayal. He could also use this experience to grow even stronger and more determined to prove himself and his beliefs.
Naruto would be heartbroken. He might initially be in denial, not believing that his mother could forget him. Then he would probably get angry, vowing to find out who or what caused this and make them pay. After that, he'd turn his anger into determination and start looking for solutions to bring back her memories.
At first, Naruto might be extremely shocked. He has always seen Tsunade as a respected figure. So when she hurts him, he may not be able to immediately process it. He could be speechless and just stare at her in disbelief.
As he grows up, Naruto could become very angry. He might develop a sense of abandonment and this could fuel his determination to become stronger. He would want to prove himself to his mother, wherever she is. In this fanfiction, his anger could be a driving force in his character development.
Naruto's reaction could be complex. On one hand, he would be extremely excited. But on the other hand, he would be worried about the consequences. He has learned about the balance of the ninja world and might be afraid that bringing Kushina back could have negative impacts. However, his love for his mother would probably overpower those concerns in the end, and he would still strive to make her return a reality.
Naruto might initially be shocked. Given his friendly nature towards Sasuke in the original story, he wouldn't expect such an attack from her. So, his first reaction could be pure disbelief.