How does Brooks present Martyn's and Alex's relationship?

If this novel were a film noir, and if sixteen year old Alex was a few years older, she would be described the same way as such women in such films are - as a "femme fatale". This is a woman (or in Alex's case, a young woman) who knows she's in trouble or attractive, often both, and uses a hapless, well-meaning man to achieve her often murderous ends. Calculating and self-centered, the femme fatale is a user, a liar, and a temptress, someone with drive and determination but whose intentions and actions are defined more by selfishness than compassion or affection. Alex is all these things - at least, as the narrative unfolds. The question of whether she does what she does solely in response to the situation at hand or whether she's a user at the core of her nature is unclear - can one answer this question by looking at her relationship with Dean? She says she's never been happy with him, but because she's so devious about so many other things, one might very well wonder. Her later actions certainly seem to suggest that she and Dean are more alike than she and Martyn, which is maybe why she decides to get rid of him (Dean) - she feared being used by him as much as he might end up being used by her. In any case it's all speculation, albeit of the intriguing sort. The bottom line is Alex uses and discards Martyn with no regard whatsoever for his dreams, feelings, goals and values, and for that she more than earns the sobriquet "femme fatale."

It's interesting to note, however, that Martyn's portrayal of her is, to some degree, colored by what appears to be lingering affection for her.