Recently, I have stumbled upon a problem. After releasing an issue, I think that I failed to earn the trust of my readers. My analysis is that they did not have enough faith in me to make the "right choices" about my story. Let me explain:
One of my protagonist closest friend is a traitor secretly working for the bad guy. He plans to kill the hero, and the reader is not aware of that. I have made sure that he looks like a genuine sidekick, though there is plenty of evidence that suggests he will do something.
Before a battle, he ultimately poisons the hero with a unique type of toxin designed to induce bloodlust and insanity amongst men. I introduced a Chekhov's gun just before to showcase the moment Traitor poisons the hero, but nothing is explicit, a.k.a. the reader does not know that the hero has been poisoned. Then, during the battle, the hero goes on a rampage and kills people from both sides due to the effect of the poison. An action which causes him to lose most of his support and makes him question everything he has been fighting for.
Following this event, he will find a way to win without fighting because he fears to lose his mind a second time. It's only later that we learn the hero rampage was caused by the poison, and that it was all Traitor's fault.
The scene during which the protagonist goes insane was all but successful. Instead of asking themselves "what happened", "why did the hero do that", the readers came with critics like "the hero would never do that", "it makes no sense" or "the story lost its potential". Moreover, if I try to bring the poison and explains it all now, it will sound forced and as if I was trying to "make up" for my mistake (even though it was definitely planned!).
I am confused about this reaction, and I don't know how to handle it. I don't think the plot is the cause. The hero had to go through this trial, and the traitor had to provoke it. Yet, I have been wondering what went wrong. The explanation I came with is that I did not build enough trust. Which begs the question:
What should have I done to have the readers trust me and my story?