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.
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 possible reason could be a misunderstanding. Maybe his mate misinterprets something Harry does or says. For example, if Harry is often away on dangerous adventures, his mate might think he doesn't care about their relationship and reject him.
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.
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 possible reason could be some sort of external threat. Maybe there's a dark force that wants to use his mate against him, so to protect her, he's forced to reject her. For example, if there are dark wizards who plan to capture his mate and use her as a bait to get to Harry, he might think rejecting her would keep her out of danger.
One possible reason could be that Hermione is too focused on her studies and career goals in the wizarding world. She might see a relationship with Harry as a distraction. Another reason could be that she has different values when it comes to love. Maybe she wants someone more like her, who is more into books and intellectual pursuits all the time, while Harry is more action - oriented.
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.
One possible reason could be that Erza is focused on her own goals and career in the Fairy Tail guild. She might see a relationship as a distraction at that moment. For example, she is always striving to be stronger and take on more challenging missions. Another reason could be that she may not view Natsu in a romantic way but more as a close friend and guildmate. Maybe she has a different ideal type in mind, someone more calm and studious rather than Natsu's brash and impulsive nature.
In the fanfiction, it might be that Naruto had different ideals and goals from his family. His strong will to pursue his own path of becoming Hokage, for example, could clash with the family's expectations, causing him to reject them.
One possible reason could be that there are cultural differences between Harry and the elf. Elves might have different values and traditions when it comes to relationships. For example, their society might have strict rules about mating or partnering with non - elves.