How can I bring my spouse in the US by a second marriage?

If you already have become a Permanent Resident (have obtained a "Green Card") through your 2012 marriage, then becoming divorced would not terminate that statute and so there would be no need to file a new "Green Card application." If your approved application from your 2012 marriage was only for Conditional Resident Status (sometimes called a "Conditional Green Card" or "two-year Green Card"), and you have become divorced, then it may be necessary for you to timely file an application to Remove Conditions with a request for a waiver of the usual requirement that both spouses participate in the application process. Of course, there are many other details that determine the steps most appropriate for you to take at this point. There really is no substitute for you and you to consult with an immigration attorney who, after learning all of the relevant information, could advise about eligibilities, options and strategies to attain your goals, and who then could offer legal representation in the often complex application process.