I am so sorry.  I would try and file an amended Death Certificate listing you as the spouse on same and re-file it with the correct vital records bureau in the state and county in which he died.  I would send in a copy of your marriage license and send either an affidavit or a letter that has been notarized (that is considered a sworn statement) that you wee never divorced and that you are his surviving spouse and you wish to amned the death certificate to reflect the corrected information.  Then move on with your life.  Good luck.