I'm going to start this answer with a short anecdote from my own life. When I was in high school, I had two friends suffer tragic accidents. Nobody died, but one friend got hit by a drunk driver and had to have his leg amputated. The other friend was on a motorcycle and was hit by a truck. That accident paralyzed him from the waist down.

This was more than twenty years ago, but I still remember two distinct reactions in both cases. The first reaction was complete disbelief. I thought people were playing a cruel joke on me. Once reality sank in, anger took over. I was angry at what I considered the injustice of the entire situation. It wasn't their fault, but they paid heavy prices. I read Bridge to Terabithia for the first time years after these events from my life.

Jess's reaction to Leslie's death is awful to read. It's awful to read because of how true to real life his emotional response is. It perfectly mirrors true human grief and our response to tragic news that involves people we love.

Jess is told at the end of chapter 10 that Leslie died. Chapter 11 shows readers how Jess shows stunned disbelief. He even says that Leslie's death is not possible because of how strong of a swimmer she is. By chapter 12, Jess is angry at the entire situation. He's angry at Leslie for leaving him alone. He's angry that she went to the stream without him. Jess is even angry that other people are sad. Leslie was his, and how dare other people try to feel as awful as he feels.

They weren't crying for Leslie. They were crying for themselves. Just themselves. If they'd cared at all for Leslie, they would have never brought her to this rotten place.

Jess's anger eventually boils to the point where he punches May Belle. Jess's father is the one that calms him down and helps Jess begin moving toward acceptance.

Jess reacts to the news of Leslie's death in a manner in which I would expect anyone would respond to the sudden death of a close friend. His initial reaction is disbelief, and this is followed by profound feelings of grief and sadness.

He gets the crushing news after getting home from a lovely day out at the end of chapter 10. In chapter 11, we learn more about his reaction, which is initially a complete refusal to compute what his family is telling him. He turns around and runs out the door, paying so little attention that he almost gets run over and potentially killed himself. His father comes looking for him and takes him home, where Jesse goes to bed and has a dream in which he is told that Leslie is dead. In his unwillingness to face the truth, he convinces himself that being told Leslie was dead was just part of his dream, and not reality at all.

It is through this fog of disbelief and confusion that Jess hears his parents telling him that they are going to Leslie's home to pay their respects and that he should come with them. It is only when he hears Leslie's father telling his own father that they have decided that Leslie will be cremated that the terrible news really sinks in.

It's often the case that when someone hears really bad news, especially the death of a loved one, they immediately go into denial mode. And it's the same with Jess in Bridge to Terabithia. When his father brings him the tragic news that his beloved friend Leslie has died, Jess simply refuses to believe him. Apparently, Leslie was swinging on the rope into Terabithia when it snapped and she hit her head on something when she fell.

But Jess doesn't want to know the details. In fact, he's certain that his father is lying to him. Consumed by grief, poor Jess is unable to face up to the terrible truth of what's happened. The presence of May Belle at the scene makes it even harder for Jess to confront the terrible truth. May Belle believes that Leslie will go to hell as she's not a Christian. If Leslie has indeed died, then according to May Belle, her soul will be tormented for all eternity. As that's the last thing that Jess wants, he's not about to accept the fact of Leslie's tragic demise.

Even after a few hours Jess is still in denial. But a part of his mind knows that Leslie has indeed passed away. However, this doesn't make it any easier for him to deal with such a profound loss.

As Chapter Eleven shows, Jess' response to Leslie's death seems to follow a fairly typical pattern of going through a huge gamut of different emotions. Firstly, he meets the news with complete denial, refusing to believe that it can be true and feeling that if he runs away it will not be true and Leslie will still be alive, as the following quote demonstrates:

He ran until he was stumbling but he kept on, afraid, to stop. Knowing somehow that running was the only thing that could keep Leslie from being dead. It was up to him. He had to keep going.

The two short sentences at the end of this paragraph demonstrate how he has shut down rational thought, so shocked is he by the news of Leslie's death, and all else is out of his mind, only the fact that he has to keep running. The short sentences therefore illustrate his single-minded fixation on what he is doing. Then he descends into numb disbelief, before going through guilt and anger before he is finally able to begin to process what happened. One of the reasons why this book is so successful, and rightfully so, is through its realistic depiction of a child's grief.