Green card question

[tobinjames]

A South American friend of mine is currently in the midst of the application process for a 10-year green card. He's due to get it in October. In the meantime, however, his marriage of 4+ years to an American woman has hit the skids. She's currently extorting money from him, claiming that if he doesn't meet any or all of her financial demands, she will file for divorce, thereby terminating his green card application.

Is this true? He has been working legally in this country and paying taxes for over four years. Is he not afforded any kind of rights under these circumstances? Any help or insight would be greatly appreciated.