Why Dionne Warwick Will 'Never Forgive' Those Who Accused Her Sister of Molesting Whitney Houston

Nearly a year ago, a documentary about Whitney Houston, Whitney, revealed a shocking claim by her former assistant, Marie Jones, that the late singer had been molested by her cousin, Dee Dee Warwick, sister of Dionne Warwick.

In an interview in this week's PEOPLE about her life, family, music and her new album She's Back, Warwick says she is still angry about the claims against Dee Dee, who died in 2008.

"All I can say about Dee Dee is that she was a loving, caring, giving person," Warwick, 78, tells PEOPLE. "What was depicted of her is absolutely untrue and something I will never forgive."

At the time the film came out, Whitney's mother, Cissy Houston, issued a statement also on behalf of Dionne, which said that Dee Dee had been unfairly accused.

It read in part:

"We cannot reconcile the Public's need to know about Whitney's life as justification for invasion of her privacy or the charge against Dee Dee, a charge which neither Whitney nor Dee Dee is here to deny, refute or affirm. Neither I, Dionne, nor my son Michael who was very close to his sister, and in the film is VERY candid about their drug use, has ever heard these allegations; we have never heard anything remotely connected to the crimes charged against Dee Dee in the film.

Warwick, whose new album is out May 17, and her sister grew up in a musical household. Their mother, Lee Drinkard, was a member of the Drinkard Sisters, along with Lee's younger sister, Cissy Houston.

Warwick and her sister Dee Dee sang gospel in church and as young women formed their own group, The Gospelaires. As a backup singer, Warwick met Burt Bacharach who asked her to record some demos of his songs, and it was those records which launched her into stardom.

As Warwick became a superstar, she witnessed the ascendancy of her young cousin Whitney into the stratosphere. When they sang together, she says, "It was wonderful." But she stands firm in not speaking further about Whitney, who died after a long struggle with drug addiction. "I usually don't talk about her," she tells PEOPLE quietly.

As someone who has lived through her share of great triumphs and personal losses, Warwick continues to sing and perform and persevere as she always has. She included one of her most beloved songs, "What the World Needs Now Is Love" on her new album for that very reason.

"The world needs Iove," she says simply. "I hope they're paying attention this time around. It's time for that healing factor and it's called love."

For more from Dionne Warwick, pick up the latest issue of PEOPLE, on newsstands Friday.