I don't know why people hate the season 2 ending???
I think it is brilliant. This season finale makes the series become more thought-provoking and haunting than any series on TV now! If the series solved every misteries of the case, I don't think it would haunt me and make me think about it that much (maybe I will forget it just after one day)!
And if you are disapointed because of the season finale, I think you completely don't understand the spirit of the series. From the begining of the series, it never tries to explain and give us a clear answer, it is not a series that tries to solve the misteries and who is at fault. It's a series about how people are affected by a terrible crime and it's a character study series- explore the characters in a naunced and heart- breaking look. That makes the series different and become one of the best series on television.
This is just my opinion. You may disagree or agree but I hope to discuss with you more about the finale and the series.