Perhaps the father is under the influence of some external force. In fanfiction, it could be that he is being blackmailed or controlled by a dark wizard. As a result, he has to reject Harry against his true feelings. Also, it could be that the father has made some big mistakes in his life and he doesn't want Harry to be associated with him because he thinks it will bring harm to Harry.
Harry may also become more empathetic. Since he has been rejected, he understands the pain of being unwanted. This could lead him to be more understanding towards others who are in difficult situations. He might start to form closer bonds with his friends who support him, and these relationships help him grow into a more caring and mature person.
He might be initially heartbroken. Harry has always been a bit of an emotional person, so he could go into a state of depression for a while. He might isolate himself from his friends and focus only on his studies or fighting against the dark forces, using it as a way to distract himself from the pain of the rejection.
Harry could try to communicate openly with his mates. He can explain his side of the story and clear up any misunderstandings. This might be difficult at first, but it's a direct approach.
One possible reason could be jealousy. Maybe Harry has some special abilities or has received more attention than his mates, which makes them envious. Another reason might be a misunderstanding. Harry could have been misinterpreted by his mates due to some miscommunication or false rumors.
One reason could be that his mate has different life goals. Maybe she is more focused on her own magical career and doesn't see a relationship with Harry fitting into that at the moment. Another possibility is that there are misunderstandings between them. For example, Harry might have been too involved in some dangerous adventures and his mate thought he didn't value their relationship enough. Also, it could be due to external pressures, like her family or friends not approving of Harry for some reason.
He could also give his mate some space for a while. Sometimes, distance can make the heart grow fonder. By giving space, his mate might have time to think about their relationship and realize what they are missing.
It could also be due to differences in their personalities or goals. If Harry is very adventurous and his mate is more cautious, they might not see eye - to - eye on certain important matters. And this fundamental difference could lead to the mate rejecting Harry.
One reason could be a misinformation campaign. Some malicious wizard or witch might have spread false rumors about Harry, making everyone believe that he has done something terrible like being in league with Voldemort again.
Well, it could be that Harry Potter makes a big mistake in fanfiction. For instance, he accidentally endangers his mates. This would lead to them feeling angry and rejecting him. Also, differences in beliefs or goals can play a part. If Harry starts to pursue a path that his mates don't agree with, like getting too involved with a certain type of magic that they consider dangerous, they might reject him.