Whitney's success and behavior started to go downhill by 2000. She was often late for concerts and interviews, or cancelling altogether on some occasions. When she appeared on Michael Jackson: 30th Anniversary Special, she was very thin, which brought up allegations of substance abuse. The incident was brought up again in 2002, on a 20/20 interview with Dianne Sawyer. Houston addressed the allegations saying people don't know the situation, and that she makes too much money to use drugs. She did to drinking and using in the past, but denied she was thin because of it. Her fifth studio album, Just Whitney, was released in December. Although it only sold two million copies, it had the highest first week sales of any album she ever released. In August 2009, her final album, I Look to You, was the first number one album since The Bodyguard, and first studio album to reach number one since Whitney on the Billboard 200.

Whitney's team strongly recommended her not to go on tour because she was losing her voice and had to be retaught how to sing. However, she went on her final tour, Nothing but Love, from December 2009 to June 2010. Fans report that her performance wasn't up to par like her previous tours, some showed her some grace because of what she was going through. Sparkle would be Houston's last film, production began in late 2011, and was released in theaters on August 17, 2012. In the days leading up to her death, she appeared "disheveled" and "eratic". Her last performance was with Kelly Price in Hollywood, they sang "Jesus Loves Me". Tragically, on February 11, 2012, Houston was found unresponsive in her hotel bathtub at the Beverly Hilton Hotel, ans was pronounced dead at 3:55 p.m. PST. Clive Davis decided to go on with the Pre-Grammy party that night, which made an awkward atmosphere for most celebrities because the event was in the same building and her body was still upstairs.