If you have a conditional green card you are going to need to apply for a "good faith" marriage exception to remove the conditions. You will need an attorney to process this successfully, my firm handles such cases in NY.
Law Offices of Nicklaus Misiti
212 537 4407
Legal disclaimer: The statement above is general in nature, as not all the facts are known. You should retain an attorney to review all the facts specific to your case in order to receive advise specific to your case. The statement above does not create an attorney/client relationship.
From a divorce perspective you're treated like anyone else. From an immigration perspective you must demonstrate that the marriage was not for immigration purposes.
Under the rules governing the conduct of attorneys in New York it may be necessary to remind you that this answer could be considered attorney advertising.