all just a dream?

my take - frustrated housewife envious of her divorced friend's louche attitudes and more fulfilling sexuality fantasises about an affair with a young lover and the guilt associated with her forlorn musings culminate in the events played out in this thriller - i think, but not over-confidently, that prior to her daughter's birthday party amy attempts to seduce her husband but fails and he leaves on a business trip - she falls asleep and dreams what unfolds only to wake at the end of the film as her daughter's party is about to begin - i think she worries her husband won't be back in time for the party and in effect he returns just as everyone is leaving.