In some fanfictions, Elena's death could be a sacrifice. For example, she might sacrifice herself to save her friends from a powerful dark magic. This would cause great grief among Stefan, Damon, and the others, and they would have to find a way to move forward while also dealing with the consequences of her death. It could also lead to unexpected alliances as they try to figure out what to do next.
There are fanfictions where Elena and Klaus are thrown into an alternate universe. In this universe, they are the only two vampires left and have to figure out how to survive and repopulate the vampire race. This forces them to work together closely and, over time, they develop feelings for each other that are far from the hatred they initially had in the original Vampire Diaries storyline.
One idea could be that Klaus, after being away for a long time, returns to Mystic Falls and finds Elena in a difficult situation. He decides to help her out of a sense of an old, unspoken connection. As they spend time together, they start to understand each other better and a relationship begins to form.
Elena's final romantic partner in the Vampire Diaries novel is Damon. Their love story is full of ups and downs, but they overcome all odds to be together.
You might have luck looking on popular fanfiction websites like Archive of Our Own (AO3) or Wattpad. They often have a wide range of Vampire Diaries fanfics, including the type you're looking for.
In some fanfictions, Elena's autistic sister might be portrayed as having unique sensitivities. For example, she could be highly sensitive to sounds or lights, which might play a role in the Vampire Diaries' supernatural setting. Maybe she has a special connection to the vampires or other supernatural beings because of her different way of perceiving the world.
The popularity of 'The Vampire Diaries Damon and Elena Fan Fiction' is due to the intense relationship between Damon and Elena in the original show. Fans love to explore different scenarios and what - ifs for their relationship. They want to see more of their love story, and fan fiction allows for that.
She could be a source of support for Elena. In the chaotic world of the Vampire Diaries, with all the vampire - related drama, her sister's unique perspective could offer a different kind of advice or comfort.
For Stefan, Elena's death could be a huge blow. He might go into a deep depression or spiral out of control as he had always been so in love with her. Damon, too, would be severely affected. He might become even more vengeful and angry, blaming himself or others for her death.