Songfacts®:

• Written by Swedish hitmakers Max Martin and Herbie Crichlow, this pop/R&B ballad finds the Backstreet Boys struggling with feelings of loneliness after a breakup. Martin also co-produced the track with Kristian Lundin, his collaborator on the group's earlier hits, "As Long As You Love Me" and "Quit Playing Games (With My Heart)."
• This was released as the third single from the boy band's second US album, but eager fans got their first taste of the tune when it was previewed at the end of Britney Spears' debut album, ...Baby One More Time.
• The music video, directed by Stuart Gosling, reflects the real-life struggles each bandmember went through during the making of the album. It opens with Brian Littrell standing alone outside of a hospital room while doctors rush in to save a dying patient that turns out to be him. Littrell, who was born with a heart murmur, had gone through open-heart surgery to treat it in 1998.
  
  Meanwhile, AJ McLean, whose friend died in a car accident when they were teens, sits alone on a bus looking at a photo of a pretty girl. He even thinks he sees the girl walk past him, but she's just an apparition. The bus is bound for Denniz St, which is an homage to Denniz Pop, one of the band's producers who died of stomach cancer the previous summer. The vehicle is driven by a blonde-haired man who bears a strong resemblance to the late producer. The bus nearly hits a girl in the street, but thankfully Nick Carter, who was walking alone in the rain, rescues her in time.
  
  Elsewhere, Kevin Richardson, who at 19 lost his dad to cancer, watches home movies of happier times with his father (the footage isn't real; he and his dad are portrayed by actors).
  
  At a nearby bar, Howie D is sitting alone when a young woman in red runs up to him, only to disappear. The girl represents his sister, who died of lupus a year earlier. By the end of the clip, the guys converge in the street and perform the rest of the song together.
• This was nominated for the Grammy Award for Best Pop Performance by a Duo or Group with Vocals at the 2001 ceremony but lost to "Cousin Dupree" by Steely Dan.
• The Latin-American boyband CNCO paid tribute to the Backstreet Boys clip in their 2020 promo for "Hero," a cover of Enrique Iglesias' 2001 smash. The Carlos Perez-directed video borrows imagery from "Show Me The Meaning Of Being Lonely," including a lonely bus ride shot in black and white, and scenes of the guys singing together on the dark, rain-slicked streets.
• In the first week of its release, Millennium sold 1.1 million copies, breaking the record for highest first-week sales in the SoundScan era (Billboard began using Nielsen SoundScan to track album sales in 1991). 'N Sync broke the record the following year when their No Strings Attached album garnered a whopping 2.4 million sales in its debut week.
• This was used in the movies Saving Silverman (2001) and Scoob! (2020).