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/ Source: TODAY
By Eun Kyung Kim

Lady Gaga’s longtime friend Sonja Durham has died after a long battle with breast cancer.

"Watching one of my best friends in the world show unfathomable courage, strength, and positivity while battling cancer has really changed my life,” the entertainer wrote in one of several social media photos she posted in a tribute to Durham. “Thank you Sonja for inspiring me and all of us everyday with your joy."

Durham, who passed away last Friday, was a former assistant and manager with the singer’s Haus of Gaga creative team and the inspiration behind “Grigio Girls,” a song on Gaga's latest album, “Joanne.”

Last month, the singer and actress dedicated an acoustic version of her hit “Edge of Glory” to Durham while performing at the Coachella festival.

Earlier in the year, Gaga helped her friend plan her wedding and get prepared for the big day. Durham later wrote about who much the singer has supported her, financially and spiritually, in a blog post about her effort to fight her stage IV cancer, which metastasized into her lungs and brain.

"Honestly, if it wasn't for Gaga and the financial contributions from everyone so far I really do not think I would be here," Durham wrote. "Let's just say I understand why people give up and die because they do not have the resources that I have been given. It's really given me some thought on starting a nonprofit."

Gaga, 31, said during an interview last year with Radio.com that she has known Durham since she was 23.

On Sunday, she mourned the loss of her friend online, saying she felt like she had been "robbed of the last 10 years of my life, friendship and career with her. Like someone took her from us, and with that taking took all the good times,” she wrote on Instagram. “I know that's not true, and I know that I have those memories forever, I'm just in shock that I will never have new ones with her."

But Gaga also vowed she would “live everyday with more passion, more determination, more compassion and more giving than ever before” in Durham's honor, as well as for others who have lost loved ones to cancer.

"I'm a part of that family now," she said. "I vow to be a warrior for her and be a voice for cancer patients so the world can continue to improve the dialogue and the fight."

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