The thing is is can't all be acted can it? No group of friends could contain that amount of good actors. Millie especially, when she is upset you can really see it and Rosie's face freezes over and is really quite scary when she is pissed off. I don't think that it all can be acted.
I remember when I was into The Hills and read an interview with one of them where she said that it reflected what was going on in real life but they would get them to re-enact certain scenes and add some for dramatic effect.
Anyway I prefer to believe it is about 90% real, it makes me happy
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