Kelly Rowland sings the U.S. national anthem before the fight between Floyd Mayweather Jr. and Robert Guererro for Mayweather Jr.’s WBC welterweight title at the MGM Grand Garden Arena in Las Vegas, Nevada, May 4, 2013. (Steve Marcus/Reuters)

Singer Kelly Rowland has long played the role of loyal BFF to Beyonce Knowles, never showing anything but enthusiasm for the astronomical success of her friend and former Destiny’s Child groupmate. Rowland carved out a solid solo recording career after DC disbanded, but it can be hard to have proper perspective on the music of someone who is so closely allied with the world’s biggest pop star.

For those who’ve always suspected that Rowland must harbor some resentment toward Queen Bey, that there must be some trace of envy behind her sweet perma-grin and all of those perfect sound bites, you were right. On Rowland’s new single, “Dirty Laundry,” she finally gives us a glimpse of what it’s like to be Destiny’s middle child.

“Doing this song for me was so therapeutic,” she said during her show at the Fillmore Silver Spring on Sunday night. “Honesty, like my mama always says, is always the best policy.” On the slow ballad, Rowland talks about living in Ms. Knowles’s shadow, but the stuff about Beyonce almost feels like tabloid bait to bring attention to the song’s other central theme — domestic violence.

Rowland choked up when talking about how a physically and emotionally abusive partner almost destroyed her relationship with her family and her “sister,” Beyonce. “Hitting the window like it was me/Until it shattered/He pulled me out and said, ‘Don’t nobody love you but me/Not your mama/Not your daddy/and especially not Bey,’ ” she sang, letting the crowd handle some of the vocals when she was overcome by emotion.

Her voice hitched and she stopped the song, putting her head in her hands until she could collect herself and continue. It seemed to be a genuine display of vulnerability and emotion, but Rowland, for the most part, projected nothing but strength, independence and happiness during her hour-long set. She stamped onto the stage and started with a medley of her feature work — “Neva End” with Future, “Dilemma” with Nelly and “Representin’ ” with Ludacris — just to remind everyone that she is a sought-after artist.

Sunday was the first night of Rowland’s tour with singer/songwriter The-Dream, and both have new albums to plug: Her “Talk a Good Game” is slated for release on June 18; his “IV Play” drops Tuesday. The-Dream, who is masterful at stringing together notes but not always as adept at hitting them, was in fine form. He killed his set, filled with new material and his earlier hits, from “Falsetto” to “I Luv Your Girl.” He and Rowland came together for the sexy duet “Where Have You Been,” from “IV Play,” and she reminded the audience, a couple of times, that he is the mastermind behind “Dirty Laundry,” which Rowland called “the best song of my career.”

Rowland previewed other music from “Talk a Good Game,” including the derivative but lively “Street Life,” and the sultry title track, which takes Rowland out of the pop/R&B realm and more into the adult contemporary bit.

Although Rowland doesn’t have Beyonce-level smashes, or the costumes and theatrics of the Mrs. Carter tour, she does have an honest, lovely singing voice and some considerable hits, including “Can’t Nobody,” “Bad Habit” and the racier “Kisses Down Low,” as well as the Grammy-nominated “Motivation.” She also sang snippets of “Survivor” and “Soldier,” lest anyone think she was anything other than proud of her run in one of the best-selling girl groups of all time, singing alongside the biggest superstar in the universe.

Sarah Godfrey is a freelance writer.