When their eyes met across a crowded nineties bar in 2014, little did Robyn and Sean Grainger know that they would be back in Retro celebrating their romance three years later. The Cardiff couple have won Retro’s Truly Madly Deeply competition, after the nineties themed club set out to find couples who have met on its dancefloor and tell them their stories to win some romantic goodies. Retro received tens of entries but the winners were announced on…