Tax Laws in NYS

My hysband and I are getting separated this year. When I file my 2003 taxes for the year 2002, can we both file single even though we will be separated and not yet divorced?

You can file as single if, on the last day of your tax year, you are unmarried or legally separated from your spouse under a divorce or a separate maintenance decree. State law governs whether you are married or legally separated under a divorce or separate maintenance decree.