回复：want a divorce

Controling you finacially and domestic violence seems a bit of a strecth, because he is the bread-winner in the house, he might have more say about how you spend his money (except for common household spending).
Child custody, who knows, if he can prove that you married him only for the GC, you might not get anything. You have been married for more than 4 years and only wanted to divorce right after you got the GC, which does not favor you too much.

For marriage based immigration, I do think the law tend to protect citizens more. Anyway, not a legal expert, just my gut feeling. No offense inteneded, everybody has the right to choose the way of living, meanwhile, one should try not to hurt others in the process.