I like BA's suggestion to talk to a lawyer before doing anything. That way, if depositions come into play and all your friends and family say they knew he only married you for the green card, you aren't left holding the bag and trying to back track to defend yourself. From what you wrote, I can see you genuinely loved him. His motives shouldn't have a bearing on what you do, right?
It's hard to stand up to parents and other "authority" figures - especially when they're used to controlling you and getting you to "see" their way. I'd hate for you to start your 30s knowing this is a battle well worth fighting. At some point, the stakes get bigger and the issues get more difficult to navigate. You have to own your life and learn how to tell them to go to hell and look forward to the trip. (Ok, I stole that from Winston Churchill, but you get the drift.)
After all, you're not their puppet. You're a real person with real feelings and needs that are separate from your FOO.
Good luck!
Betsey
"There are only 2 ways to live your life. One is as though nothing is a miracle. The other is as though everything is a miracle."
(Ok, I stole that from Winston Churchill, but you get the drift.) 
