Jelly Roll was already looking like a single man weeks before news of his split from Bunnie XO became public ... 'cause he ditched his wedding ring during a major CMA Fest performance. The country star took the stage at Nashville's Nissan Stadium on June 6 ... and looking back at the photos now, one detail jumps out ... there was no wedding band on his finger. At the time, it didn't raise many eyebrows. Now? It tells a very different story. As TMZ first reported Monday, Jelly filed for divorce