Maybe Clay's suicidal thoughts in the fanfiction stem from a build-up of stress, internal conflicts, or feeling hopeless about a particular situation. Different authors might have their own creative explanations for this.
I think it's because fans love the show and want to create their own scenarios involving Clay and Sheri. It gives them a way to keep the story alive and explore new possibilities within the 13 Reasons Why universe.
The reason Clay was hurt in the fanfiction could vary. It might be because of a betrayal, a risky adventure, or even a random accident. It all depends on the imagination of the writer creating the story.
Maybe it's a way for the author to show the depth of Clay's internal struggles and psychological turmoil. Or it could be a reaction to specific events or relationships in the story.