This was a girl who loved to go the extra mile with the male sex. It felt great to her. She really didn't have to go with Arnold at the end, but did, because she felt it was her destiny. It was what she was working towards the whole movie. I don't believe that she couldn't get away from him - I felt she couldn't allow herself to get away from him.
I'd seen bits and pieces of this film on television. Today I saw the ending. I, too, wondered whether Dern was portraying Connie as afraid for her safety or afraid of her own desires. Both? The difference in sexual sophistication between Connie and Arnold is highlighted during their scene at her home, however, and for me that determines any sexual activity between them as being rape. Statutory rape laws exist for the very reasons depicted as we're allowed to see inside a young girl-woman's mind and heart.
It was heartbreaking to watch, personally. I remember girls like Connie from my teen years. Eager to appear grown up, eager for the knowledge and the perceived advantages, yet unaware until too late of their true needs. I've read Oates short story as well as her insights into her motivation for writing the story. If we take her frame of mind as our own, then the literal Connie sacrificed herself to rape and murder. I don't particularly care for that frame of mind.
I was glad to read Oates approval of the reconcilatory ending chosen for the film. I much prefer that ending and don't see it as a copout at all. Connie, in my opinion, was clearly changed upon her return from the ride with Friend. Whether or not he raped her was not crucial. The crucial point was that she returned open to the realization that perhaps she was okay being who she already was and perhaps her family was okay as well.
One poster stated that had Connie been raped wouldn't that have distanced her from her family, not drawn her closer? I agree. Perhaps that is why a viewer could just as easily surmise that Connie "chose" to go for the ride (i.e. have sex) in order to avoid being "raped." Borderline rape victims have described similar attempts to take control of a situation that otherwise may turn violent.
I found the dance with her sister bittersweet and touching. Like a young girl who's been stumbling around in mom's high heels and who finally stops to step out of them and just dance.
I thought that Laura Dern and Treat Williams played their roles superbly.