Thank you for playing the game! I'm glad that you enjoyed it overall. I'm sorry if the sensitive content might triggered you in some way, because I didn't really make a clearer warning about the explicit contents at the beginning.
About the endings, I'm assuming you already get 2 standard endings and one secret ending where you found a rope in the basement.
To get to the true ending, first you have to get the Pen item in the classroom in chapter 4, then you write a message on Adam's note near the swing in chapter 5. After that in chapter 11, you have to choose to let Nancy stay with her father. Then at the end of the game, you give Nancy in the real world her Bunny back. This will trigger the true ending of the game.
I don't know if you can reach to the true ending based on my guide, but if you can, I really hope you can give it a try again and see how the true ending plays out.
Again, thank you so much for finishing the game! I'm really appreciated!