Another aspect could be that within Hogwarts, there are some teachers or students who try to control Harry. Maybe they want him to follow their ideas about how to deal with the latest threat in the wizarding world. However, Harry has his own ideas based on his experiences. He might decide to form his own group of like - minded students and wizards to oppose those who are trying to control him, and work towards a solution in his own way.
Perhaps in the fanfiction, the Ministry of Magic tries to control Harry for their own political gains. They might want to use him as a symbol or force him to do things their way. But Harry refuses. He could go on the run, hiding from the Ministry and using his friends and his knowledge of hidden magical places to stay out of their grasp. He would be determined not to be a puppet for the Ministry's power games.
One possible reason could be their fundamental differences in personality. Harry is brave and impulsive at times, while Snape is often brooding and secretive. Their past interactions, which were mostly filled with animosity and mistrust, could also be a factor. Harry might not be able to see Snape in a romantic light due to all the times Snape was cruel to him in school.
One possible reason could be that Harry is still haunted by his past traumas and feels he's not in the right mental state to marry anyone. His experiences with Voldemort and the losses he's endured might make him reluctant to bring Ginny into a potentially unstable future.
One possible reason could be a misunderstanding. Maybe Harry overheard Hermione saying something that he misinterpreted, like she was criticizing his actions but in reality she was just worried. For example, if Hermione was expressing concerns about Harry's risky adventures in a way that Harry thought was her doubting his abilities.
Maybe Harry has some unresolved issues from his past, like the trauma of losing his parents and many of his friends during the fight against Voldemort. These could make him hesitant to enter into a marriage with Ginny. He might also be worried about how the wizarding world would view their marriage, especially if there are still some who oppose him or his family.
One possible reason could be that Harry might feel he's not ready for marriage. He has been through so much trauma from fighting Voldemort and might need more time to focus on himself and his own healing. Another reason could be that he might view Ginny more as a sister or a close friend at this point in the fanfiction, rather than a romantic partner.
One possible reason could be that Harry has grown tired of being Dumbledore's pawn. He might feel that he has been constantly pushed into dangerous situations for Dumbledore's grand plans and he just wants to focus on his own life and safety for once.
One possible reason could be that he's tired of the constant pressure and spotlight that comes with competing. He has been through so much already and just wants a break from the high - stakes competitions like the Triwizard Tournament. Maybe he's also seen how competition can bring out the worst in people and doesn't want to be part of that.
One possible reason could be that Harry might feel he's been used too much in the past by Dumbledore. He could be tired of being thrust into dangerous situations without having a full understanding of the whole plan. For example, in the original series, he often felt like he was just following Dumbledore's orders blindly and it led to great personal risk and the loss of some friends. So in the fanfic, he might have decided enough was enough.
One great 'Harry controlled fanfiction' could be those where Harry masters a new and powerful magic. For example, a story where he discovers ancient spells that allow him to control the elements, like summoning storms to protect Hogwarts. This kind of fanfiction often adds an exciting new dimension to the original Harry Potter universe.
One possible reason could be fear. Maybe he's heard some scary rumors about Hogwarts, like the Forbidden Forest being full of dangerous creatures. Another reason might be that he doesn't want to leave his normal life behind. He has friends in the Muggle world and he might be reluctant to give that up for a world full of magic that he doesn't fully understand yet.