Full of Unexpected Events

We were Liars was the book our English class has read for a month and eventually we finished reading it. Although I didn't read it carefully because of the schedule conflicts and making up quizzes, this book was fun to read. Especially it was fun to predict the next story. I remember the class time when our classmates talked about their opinion about the ending and their prediction. The ending of this book was extremely tragic and unpredictable, our discussion was longer than usual discussion I guess. Nonetheless one of our classmates actually succeed to predict, which was pretty impressive and even made our teacher shocked. Anyway, I liked the novel. 

The process of choosing this book was completely different from any other books we have read so far. To celebrate our last marking period as well as the end of the school year, we accepted the suggestion system and voting system which were very respectful and democratic. The book that was chosen is called We were Liars which looked like it has some similar parts to the previous book Me and You according to the description of the book that was on the book website. 

I expected kind of different ending. I didn't think it would be happy ending though but I thought Cadence was really injured and three of other liars were bullying her. Three other liars were pretending to be her friend by agreeing in front of her and talking in favorable way. However in fact they made the accident on purpose to harm Cadence. I didn't know that the ending will be this sad. I think Cadence dropped the fire by mistake and was so shocked so she just got out from the house justifying her action by assuming other liars would already be in meeting place otherwise it is not reasonable to me. I think, also, Cadence will live in suffer of survivor. I don't think the fire accident happened because of her but also every one's stupid, mischief, and thoughtless behavior.
If they thought one more time before they have done it which cannot be rewinded, and if they weren't drunk so they could think normally, would things be different?