I certainly didn’t think there was any truth to this matter. We would have known by now, if they were dating. According to SFGate.com:
The mix-up happened when “2 Fast 2 Furious” star Tyrese proposed to his girlfriend, Norma, at a baby shower party Brandy threw at her Los Angeles home on June 7.
Barnes [Brandy's Publicist] says, “There’s no truth to the rumors Tyrese proposed to Brandy; he actually asked his girlfriend to marry him during the shower.”