Found some unused Anna dialogue which goes more into her initially negative attitude: https://dl.dropboxusercontent.com/u/43719925/Anna Unused.wav
Her character had potential. It's a shame she was so underdeveloped as a character, I would have much rather heard this spiel at the beginning instead of her jokes about being a good rabbit and mating with Dark Ones.
Her script is different in the Russian dub and she explains the reasons why she was giving you a cold shoulder in the Undercity chapter. Hunter was her mentor and, it's safe to assume, a romantic interest. Artyom indirectly caused his death and she didn't get revenge since "she wasn't at the tower, targeting the Hive with the missiles".
That could be a problem in that the story is based on a book. If the new book follows the last light story closely, and involves the relationship between Artyom and Anna it could be developed during the time your quarantine. (which i think is supposed to be longer than is shown)
The voice recording and mocap were done separately and that's the problem. Listen to her monologue in Quarantine level while imagining her sitting there with a thousand-yard stare.
The same can be said for nearly every character in Last Light, with the exception of Pavel and the Dark One...
