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A lot has changed since Joan Rivers got into comedy - Mindy Kaling, Kristen Wiig, Sarah Silverman, and loads of other female comics have made it clear that women are funny - but she remembers the days when she was treated like week-old leftovers.

In an essay for the Hollywood Reporter, Rivers, 79, opened up about not being one of the boys and her falling out with Johnny Carson, for whom she guest hosted for years on "The Tonight Show."

"My group was Woody [Allen] and George [Carlin] and Richard Pryor and Bill Cosby. Rodney Dangerfield. Dick Cavett," she said about the comedians she came up with. "But I never was one of the guys. I was never asked to go hang out - I never thought about it until later. They would all go to the Stage Delicatessen afterward and talk. I never got to go uptown and have a sandwich with them. So, even though I was with them, I wasn't with them."

According to Rivers, she landed on "The Tonight Show" after a male comic on the show bombed and Cosby told a producer, "Joan Rivers couldn't be any worse than this guy. Why don't you use her?"

"I adored Johnny," she said. "In the '70s, I did opening monologues, I was hosting. The turning point was when I left the show. Everybody left the show to go to do their own shows. Bill Cosby. David Brenner. George Carlin. Everybody. I stuck around for 18 years. And they finally offered me my own late-night show."

"The first person I called was Johnny, and he hung up on me - and never, ever spoke to me again. And then denied that I called him. I couldn't figure it out. I would see him in a restaurant and go over and say hello. He wouldn't talk to me."

She finally decided, "I think he really felt because I was a woman that I just was his. That I wouldn't leave him."

"Looking back, and I never like to say it, the Carson breakup hurt me a lot, without realizing it," she added.

Rivers lamented how men in show biz still sideline aggressive women - "If I were a man, they'd say: 'So brilliant. He's tough, but he's right.' Nobody ever says to me, 'You're right.'"

But she encouraged female comics to keep at it and ignore the competition: "A Mafia guy in Vegas gave me this advice: 'Run your own race, put on your blinders,' Don't worry about how others are doing. Something better will come."

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