I'm an American male living in London - and since moving to Europe, I have realised that most of my fellow Americans know NOTHING about the rest of the world. The reason is that most my country men and women don't bother getting off their lazy asses to go see what's out there - they just pass judgement without bothering to understand anything about the rest of the world.
I have also realized that, with all the 'freedom' American women enjoy, they are the most depressed and miserable women in the world. Take this from the opinion of a man who's spent over 20 years of his life in America.
Don't pass judgement on other cultures unless you bother actually going out and trying to learn a bit about them. This girl may have been forced into a marriage - but if you ask her 10 years down the line, she may tell you it was the best thing that ever happened to her (many do). In contrast 60% of American women, who had the 'freedom' to choose their husbands will end up divorcing them, and saying it was the worst thing they ever did.
In addition, Afghan culture doesn't lead to an obesity epidemic, a depression (and anti-depressant) epidemic, and a work a haulic lifestyle.
Each culture has it's good and bad - don't judge and make yourself feel better by tearing down others.