Cause if nessa is one of the main characters and ita from her pov then of course josh will look bad since thats how nessa sees him. They had a toxic relationship which means she saw basically the worst side of him, her view of him is gonna be centered around that. She doesn’t see the josh she originally started dating anymore, she sees the josh who cheated on her, who was manipulative/gaslighting her, the josh who made her feel inadequate and “hard to love”. In no way am i trying to call Josh a bad person. That is just one side of him and nessa was no angel either, im just trying to explain why (most not all) naden books give that perspective. Also there are some whos authors just hate josh so they make him the bad guy.