Was the rape scene really necessary?

Needless to say, I was horrified when watching that scene. I almost wished I was watching an American movie in which the cops would just show up or the boyfriend would grab a gun and start shooting... I have been thinking long and hard about why we were shown that girl's rape and murder, and I think I see why. The whole film, we understand that something is going to happen to either her or her cousin. Showing us this murder in all its brutality gives a human face to the whole tragedy. It's a (cheap, ok) way to get us involved and to make us suffer. When she dies, we grieve as if she was family. A bad movie would have chosen a victim with whom we would not have sympathised. This movie chose to make us feel anguish and pain. So... I think it was necessary.