EXCLUSIVE: Sheila E. on Prince: 'He Was in Pain All the Time, but He Was a Performer'

Sheila E. reflects on her relationship with Prince.

Sheila E. is opening up about the time she spent with the late icon, Prince.

ET's Nischelle Turner caught up with the 58-year-old "A Love Bizarre" singer in Chanhassen, Minnesota, where she gave insight into the notoriously private artist. Sheila E. and Prince famously collaborated together on one another's hits, and were once engaged.

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Sheila E. says that Prince definitely suffered pain from years of performing, and did have problems with his hip.

"I mean, you think about all the years he was jumping off those risers," she recalls. "They were not low -- they were very, very high -- and to jump off that ... First of all, the Purple Rain tour and the way that they were stacked, he had those heels on. We did a year of touring [and] for him to jump off of that -- just an entire year would have messed up his knees."

"He was in pain all the time, but he was a performer," she adds.

A source very close to the situation tells ET that Prince had the flu that turned into walking pneumonia before his death, and he was also dealing with a hip injury and had a problem with the pain killer, Percocet. The source says his issue with the powerful narcotic went back years, beginning shortly after he had hip replacement surgery in 2010.

Clearly, Sheila E. is devastated by Prince's death. When asked if she's thought about how she's going to say goodbye to her close friend, she replied, "I don't know if I can."

"My emotions, you know, I'm trying not to process it," she admits. "I'm trying to ignore the fact it is true, and I'm not looking at television. I can’t see his face on television. It's just surreal, and it makes it reality when I see it."

Sheila E. and Prince met in 1978, and while she says there was an immediate friendship between the two, there wasn't an instant attraction.

"It just kind of gradually happened, it wasn't forced," she says about how their relationship turned romantic. "We just like a lot of the same things, and then things we didn't agree on were good things we were glad we didn't agree on."

"We were both very competitive and always tried to outdo each other -- with everything from clothes to playing ping pong and basketball and pool, who could stay up the longest and record and, I mean, there's just a lot of crazy moments," she also recalls. "This was 38 years of stuff with him."

Sheila E. calls the singer "very kind and gentle."

"I fell in love with his music, and then watching him perform onstage ... forget about it, it was over," she smiles.

As for Prince's spiritual beliefs, Sheila E. says that they changed over the years. The "Raspberry Beret" singer was raised a Seventh-day Adventist and later became a Jehovah's Witness.

"When we were friends, his beliefs were different than what they are now, and that's part of change -- part of growing, part of searching and trying to find out," Sheila E. reflects. "Did he find his purpose, you know, what does he believe in or what does he not believe in? He went through all of that."

But most of all, she remembers Prince's incredible work ethic, and his drive to always be better.

"He did his homework. He created, he rehearsed, he practiced, he always gave it his all, 150 percent every time," she stresses. "He expanded and continued to move forward. He never stayed in the same place musically. It was limitless, the things that he could write and create."

And he was never afraid to be innovative.

"He said, 'I'm thinking outside the box -- I'm gonna do what no one else has done and everyone would like to do, that a lot of people can't comprehend,'" she says. “Some people don't like change and he was able to do and be whoever he wanted to be."

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Prince's autopsy was completed on Friday. He reportedly suffered a drug overdose just a week before his death, according to TMZ, when a private jet carrying the singer was forced to make an emergency landing in Moline, Illinois.

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