One sad story is the death of Sirius Black. He was like a father figure to Harry, and his sudden death in the Department of Mysteries was tragic. Harry had to watch him get hit by Bellatrix's spell and disappear through the veil. It was a moment of great loss for Harry, who had finally found a family member in Sirius.
The death of Dobby is quite heart - wrenching. Dobby, the free - elf, was so kind and helpful to Harry and his friends. He died saving them from Malfoy Manor. His last words, about being a free elf, were both a statement of his new - found freedom and a sad goodbye, leaving Harry and the readers mourning his loss.
One sad story could be about a character who was left behind after the Battle of Hogwarts. They might have lost all their friends and be struggling to find a purpose in life. They wander the now - peaceful halls of Hogwarts, haunted by memories of the war and those they've lost.
There are fanfics that focus on Snape's unrequited love for Lily in a very sad way. For example, some might explore his internal thoughts and feelings more deeply, showing his pain and longing as he watches Harry, a constant reminder of what he lost. And then there are those that deal with the death of Sirius in a more emotional and in - depth way, like how it affects Harry not just immediately but also in the long run, his trust issues getting worse.
One sad Harry Potter fanfiction could be about the death of a beloved character like Sirius Black, exploring Harry's grief in more depth than in the original books. Another might be set in an alternate universe where Harry fails to defeat Voldemort and has to live in a world full of despair. There could also be a fanfiction focusing on Harry's lonely childhood before Hogwarts, delving into his feelings of isolation.
One sad Harry Potter fanfiction is 'The Lost Years'. It delves into Harry's post - Hogwarts life filled with loneliness and the memories of those he has lost. Another could be 'A Broken Bond' which focuses on the fractured friendship between Harry and Ron due to a misunderstanding. There's also 'Silent Screams in Hogwarts' that shows the hidden pain of the students during the dark times at the school.
One characteristic could be the death of beloved characters. For example, if a fan fiction has Hermione dying, it would make the story really sad. Another could be the failure of the main characters' goals. Maybe Harry fails to defeat Voldemort in the fan - made scenario and the wizarding world falls into eternal darkness. Also, the loss of friendship or love can be a feature. If Ron betrays Harry out of jealousy, it would create a very sad atmosphere in the story.
The story of Hagrid's expulsion from Hogwarts when he was young is sad. He was wrongly accused of opening the Chamber of Secrets. He had to leave the place he loved so much at a young age, and even though he was later allowed to return as the gamekeeper, that initial expulsion and the unjust treatment he received was a sad part of his life.
One 'Harry Potter is sad' fanfiction could be 'The Lost Hope of Harry Potter'. In this, Harry might face the death of a very close friend in a more tragic way than in the original series, which makes him sink into deep sadness. Another could be 'Harry Potter's Lonely Path' where he feels isolated and misunderstood, leading to his melancholy state.
One sad Harry Potter fanfic is 'The Boy Who Lived in Darkness'. It delves into the aftermath of the war, where Harry is haunted by the losses. He struggles to find his place in a world that seems so different. The story shows his internal battles with depression and the loneliness that comes with being a hero who has sacrificed so much.
Betrayal is a big theme. When Harry is betrayed by someone he loves, such as a teacher or a fellow student, it causes him great sadness. It breaks his trust and makes him question everything. Also, the theme of unrequited love can be seen. If Harry has feelings for someone who doesn't return them, it adds to his sadness. In some fanfictions, his love for Ginny might be unreciprocated, leading to his heartbreak. Additionally, the theme of feeling like an outcast, not fully belonging in either the Muggle or wizarding world, can make him sad.
I'm not sure of specific titles off - hand, but you can search on fan - fiction websites like Archive of Our Own. Look for tags like 'angst', 'tragedy' or'sad' in the Harry Potter section. There are likely to be many stories that fit the bill there.