Hills like White Elephants

Okay so to start off, the first time I read this story it confused me. A lot. I had no idea what it was really about, especially when the guy says "to let the air in"... Let the air in where?! And to be completely honest, I thought he was talking about something completely different than what it actually was. At first I thought maybe a lobotomy, you know where they drive an ice pick into your eye/brain? Technically that would let the air in somewhere. Then I thought that would be far too brutal, but I suppose anything is possible. Then I absentent-mindedly thought maybe a boob job, 'cause you never know. But that wouldn't be letting "air" in per se, but more like silicone... Or whatever they put in there. I don't really fully understand the procedure, but either way that's not what the story was about. It was only until another person in the class piped up and said "I think it's about abortion" that I actually realized how well it fit. Anyway, so this story is about abortion. Basically it's about this couple who's sitting at a train station discussing it, but it seems like the American man has already made up his mind. The young girl, however, seems to be at a crossroads as to if she wants to actually keep the child or not. The man keeps reassuring the girl that it's a simple procedure with no risks, and that it's just "to let the air in" (which makes a lot more sense to me now).
I can see why the girl is on the fence about this subject, I mean it's probably not the easiest thing to give up a child. I wouldn't know first hand, obviously, but I can guess it's going to take a lot more thinking that just over a few drinks at the train station. And I'm sure there could be a million different reasons why abortion is bad, and people all have different opinions on the subject (I think it depends on the circumstances, not saying it's right or wrong). But this young girl is obviously suffering from a lot of internal coflict, whereas the man is certain he doesn't want this child. Now, the part I really liked about this story was the fact that it's clear that the train station represents the choice they have to make. One side of the tracks is barren and dry (white elephants), which would symbolize her getting the abortion, while the other side is lush, green, and fertile. The green side obviously symbolizes her fertility and choice to keep the child, which she seems to be leaning against. Who knows why the man doesn't want the child, there could be many reasons. Maybe the girl is too young and it would be frowned upon, or maybe she's colored and the man doesn't want that attachment to her. Maybe he's married and this young girl was his mistress, maybe he was fooling around with her behind his wife's back and got her pregnant. He would obviously not want to keep a love child, and an abortion would obviously be the easier choice for him.
In the end though, the girl picks up her things and moves to the green side, suggesting that she decides to keep her child.