Gabourey Sidibe isn't holding anything back.

After battling depression, anxiety and bulimia and undergoing weight-loss surgery nearly a year ago, the Empire star is opening up about all of it for the very first time in her new memoir, This Is Just My Face: Try Not To Stare.

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Ahead of its release on May 1, the 33-year-old actress explained why she decided to secretly get laparoscopic bariatric surgery last May in an interview with PEOPLE.

"I just didn't want to worry," Sidibe said, noting that she tried to lose weight naturally before undergoing the procedure. "I truly didn't want to worry about all the effects that go along with diabetes. I genuinely [would] worry all the time about losing my toes."

The outlet also obtained an excerpt from the memoir, in which Sidibe talks about how her "lifelong relationship" with food had to change.

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"My surgeon said they'd cut my stomach in half," she writes in her book. "This would limit my hunger and capacity to eat. My brain chemistry would change and I'd want to eat healthier. I'll take it!"

"The surgery wasn't the easy way out," she adds. "I wasn't cheating by getting it done. I wouldn't have been able to lose as much as I've lost without it."

Sidibe also admits it's taken her years to realize "that what I was born with is all beautiful."

"I did not get this surgery to be beautiful," she continues. "I did it so I can walk around comfortably in heels. I want to do a cartwheel. I want not to be in pain every time I walk up a flight of stairs."

The New York City native says that despite her change in appearance, she knows her beauty "doesn't come from a mirror."

"There's nothing ugly about me," she writes. "Anyone trying to convince me that I am -- and it's usually me -- is wasting her time. I was in a war with my body for a long time. If I'd started treating it better sooner, I wouldn't have spent so many years hating myself. But I love my body now."

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