Harry could also be very cautious around her. If she has shown that she can betray him once, he'll be on guard. He might try to find evidence to clear his name if she's spreading false rumors, and at the same time, he'll be looking for ways to protect himself from any further harm she might cause.
Once he realizes she's truly against him, he could become angry and feel a sense of deep hurt. He might start to isolate himself, not knowing who else he can trust. But also, his Gryffindor courage would likely kick in, and he'd be determined to find out why she betrayed him and try to fix the situation if possible.
At first, Harry would probably be in shock. He has always considered Hermione one of his closest friends, so her betrayal would be a huge blow. He might not believe it at first and try to reason with her.
Harry would likely be deeply hurt. He has been through so much already, and this betrayal would be like another stab in the back. He might initially go into a state of shock, not believing that someone he loved could do this to him. Then, he would probably become very angry. His trust would be shattered, and he might lash out, not just at her, but also at those around him who he feels might have known or been involved in some way.
He could also feel a great sense of anger. After the shock wears off, he might lash out at Ginny, demanding an explanation for her actions. His anger could be so intense that it might cloud his judgment for a while.
At first, Harry might be confused. He would try to figure out what went wrong. He might search his memory for any signs that could have led to this betrayal. Then, he would likely experience a range of emotions from sadness to rage. Depending on the nature of the betrayal, he could either try to win them back by showing them the truth or decide that they are no longer worthy of his friendship and focus on his own path, maybe even leaving the wizarding world for a while to clear his head.
He could be initially shocked. Harry, who has trusted Ginny deeply, would find it hard to believe at first. He might go through a period of denial, trying to find excuses for Ginny's actions.
Harry might react with shock. If he overhears something unexpected like Ron and Hermione confessing their love for each other, it would be a big surprise. He might stand there frozen for a moment, not knowing how to process it.
Harry may also get angry. He could lash out at the person who he believes has betrayed him. For instance, if it was Ron, he might shout at him and say things he doesn't really mean in the heat of the moment. This anger would be a result of his deep - seated hurt from the betrayal.
He might be extremely angry and confused. After all, parents are supposed to be the ones you can trust the most. He could start to question everything he knew about his family and himself.
Harry could initially be in shock. He's always counted on Hermione, so her abandonment would be a huge blow. He might feel a sense of betrayal and confusion.
Hermione would most likely be very touched. Harry is her good friend, and this gift shows that he really understands her. Owls are not only practical but also a symbol of the wizarding world. She would immediately start to name it and make a cozy place for it in the Gryffindor common room. She might also show it off to Ron, with a big smile on her face.
He could get angry at Hermione for not believing in him. Maybe he would storm off and then later try to prove his innocence by showing her his study methods or the source of his newfound knowledge. He might also feel betrayed since Hermione is one of his closest friends and her accusation is a serious one.