Everything in a dream represents something. The people with guns represent the subconscious trying to protect itself. In Cobb's dreams, he is tormented by his past and therefore sees his wife and kids I think. His wife isn't actually there obviously, it's Cobb's own subconscious fighting. I haven't seen the film, but what I understood was that his wife is trying to get him to stay in the dream world (could be very wrong, just what I heard). That's not actually her, that's the part of Cobb that wants to. It's like in the show Dexter, he sees his dead father who expresses doubt about his actions, that's not actually his father, it's part of Dexter's subconscious. So I always kinda thought that his wife playing with his head represented his own internal struggle.

I will definitely look at that particular character differently now as I watch the movie, however, thanks for easing my concerns. When Leo says "at the end of the film..." I was just like.. WTF!!!111!!!11".