Lady Gaga is mourning her longtime friend and collaborator, Tony Bennett, who passed away at age 96 on July 21.

"I will miss my friend forever. I will miss singing with him, recording with him, talking with him, being on stage together," the "Poker Face" singer wrote in a lengthy Instagram post Sunday (July 30).

"With Tony, I got to live my life in a time warp. Tony & I had this magical power. We transported ourselves to another era, modernized the music together, & gave it all new life as a singing duo. But it wasn't an act. Our relationship was very real. Sure, he taught me about music, about showbiz life, but he also showed me how to keep my spirits high and my head screwed on straight," Gaga continued.

The singer shared that Bennett would often tell her to look and go "straight ahead."

"HHe was an optimist, he believed in quality work AND quality life. Plus, there was the gratitude... Tony was always grateful," she explained.

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Gaga noted that aside from singing jazz music with "with the greatest singers and players in the world," Bennett also served in World War II and marched with Martin Luther King, Jr.

"I've been grieving the loss of Tony for a long time. We had a very long and powerful goodbye. Though there were [five] decades between us, he was my friend. My real true friend. Our age difference didn’t matter ... in fact, it gave us each something neither of us had with most people," Gaga wrote.

Gaga shared that Bennett's experience with Alzheimer's disease was a "painful" but also "really beautiful" era, writing, "All I wanted was for Tony to remember how much I loved him and how grateful I was to have him in my life. But, as that faded slowly, I knew deep down he was sharing with me the most vulnerable moment in his life that he could ... being willing to sing with me when his nature was changing so deeply."

"Take care of your elders, and I promise you will learn something special. Maybe even magical. And pay attention to silence — some of my musical partner and I’s most meaningful exchanges were with no melody at all," Gaga concluded.

See Lady Gaga's touching tribute to Tony Bennett in full, below:

The pop star first collaborated with legendary jazz singer Bennett on his second duet album, Duets II, in 2011. They performed the song "The Lady Is a Tramp."

In 2014, the pair collaborated on a full album together titled Cheek to Cheek, which won Best Traditional Pop Vocal Album at the 2015 Grammy Awards and also debuted at No. 1 on the Billboard 200 chart.

Gaga and Bennett released Love for Sale, another collaborative album, in 2021. It became Bennett's 61st and final studio album. The album won Best Traditional Pop Vocal Album at the Grammys, just like their first project together, as well as Best Engineered Album, Non-Classical.

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