Bobby Brown -- Performs at Soul Food Festival ... Everyone Goes Through Heartache (VIDEO)

Bobby Brown was an enormous hit at the Soul Food Festival Saturday night ... and he moved the crowd to tears as he opened up about the hard time he's going through.

Bobby said there was never any question about him fulfilling his obligation to appear at the festival. As you know, his daughter, Bobbi Kristina, lay in an Atlanta hospital, clinging to life. It's been 2 1/2 months since Bobbi Kristina was rushed to a hospital after she was found submerged in a bathtub.