Joan Rivers always appeared happy as ever when she was alive, but the comedian battled a lot of inner sadness that caused her to change her appearance with plastic surgery.

The new book Last Girl Before Freeway: The Life, Loves, Losses and Liberation of Joan Rivers, written by Leslie Bennetts, revealed the emotional turmoil the late star faced that led her to undergo multiple cosmetic procedures (she once joked she had 739) during her lifetime.

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Joan in 1960 (left) and 2014 (right).

“She grew up chubby and plain,” Bennetts wrote of Joan, who tragically died in 2014. Her mother was constantly mocking her weight and doubting her ability to succeed. “She has no talent,” Joan overheard her mother say. “She’s throwing her life away.”

MORE: Joan Rivers' Daughter Melissa Opens Up About Her Mother's Death — See What She Revealed

Between her mother's negativity and thinking her sister, Barbara, was "prettier and smarter" than her, Joan soon became obsessed with making herself over. Valerie Frankel, co-writer of Joan’s 2009 book, Men Are Stupid… And They Like Big Boobs, confessed, “Surgery made [Joan] feel better about herself."

For more on Joan Rivers, pick up the latest issue of Closer Weekly, on newsstands now!

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