Necessity of Rape scene

I watched this movie yesterday. I have to be honest that I felt like a pedophile until that rape scene. I don't know about the effect that the scene would have on Dakota Fanning but the effect that it will have on the audience will be extra-ordinary. Its almost the same feeling that I got when I first watched Boys Don't cry and it really hurt for few days to know that someone had undergone so much pain. Such movies are required to be made once in a while which can make its audience think once again. The whole time while watching the movie I was thinking about the children who had to really go through an abusive life. I felt criminal for not doing anything about it similar to the feeling that I had when watching Boys Don't Cry.
I was afraid of myself and I compared myself to all the characters in the movie to find a similarity, luckily I did not find one. But what if in some other life I had become like the boy who raped the actress or the boy who unwittingly led her to get raped or a father who failed to be a good father.
Such movies makes you doubt yourself and you only try to get better after watching such a movie and feel the need to love and respect everyone else without any prejudice. It also makes we wonder about the children who are currently going through an abusive life and some living in even more abusive conditions. What's the solution to whole problem?
Anyways, I think I am hardly concerned about Dakota because her tremendous acting ability shows that she is mature enough to cope up with the scene and situation and I dare say more than many 50 years old and above. I girl should not have been required to do such scene but more importantly no girl/boy should have the abusive life that many children have to go through.
I thought Dakota acted really well in this film and she will prove to be a really good actress in her later years.