The R&B singer, 43, went ahead with a planned concert in Mississippi with his famed group New Edition as news hit that Houston had died at age 48 in her hotel room at the Beverly Hilton in Beverly Hills.
After reportedly breaking down backstage pre-show, Brown (who shared daughter Bobbi Kristina, 18, with Houston) declined to join his bandmates for the opening song. According to a concertgoer, he then went onstage for the second song to massive cheers, singing "Hit Me Off" with gusto.
At the end of another song, Brown shouted "I love you, Whitney!" and blew a kiss to the sky, looking visibly teary.
Despite their volatile relationship, Houston told Oprah Winfrey in 2009, "I loved him so much...He was my drug. I didn't do anything without him."
Authorities reported Saturday evening that "no signs of foul play" were behind Houston's shocking passing, and her cause of death remains unknown. She entered rehab for drug and alcohol addictions last May.