One of my best girlfriends is in an arranged marriage and there's not much that can really be done about it. To be honest I'm trying to see some good that comes out of it, because well, in a few years that will be her reality.
Rather than telling her how terrible I think it is, so that when it happens she's left thinking "why me, when all my friends are free from this kind of pressure?" I've tried to look at the good in it.
I'm all for making your own choices, but as these circumstances are unavoidable, what's the use in making things more ominous and scary for a person going through the process. Until (and unless) I am in her position I can't fully understand the concept of someone choosing the person i spend my life with, however I will support her no matter her family's decision because she is my friend, and standing by your mates is what I believe to be right.