Lady Gaga paid tribute to her friend and musical collaborator Tony Bennett on Sunday following his death earlier this month. “I will miss my friend forever,” Gaga wrote in an Instagram post along with a picture of them in an embrace. “I will miss singing with him, recording with him, talking with him, being on stage together.” Bennett died at the age of 96 on July 21 after he was diagnosed with Alzheimer’s disease in 2016. “I’ve been grieving the loss of Tony for a long time,” Gaga added. “We had a very long and powerful goodbye. Though there were 5 decades between us, he was my friend. My real true friend.” She also said she’ll “never forget” the experience of working with Bennett, including on his final album. “I’ll never forget Tony Bennett,” Gaga wrote. “If I could say anything to the world about this I would say don’t discount your elders, don’t leave them behind when things change.”