Naya Rivera gets deeply personal in her new tell-all, Sorry Not Sorry: Dreams, Mistakes, and Growing Up, and she sat down with ET's Nischelle Turner at her home to dish on some of the juiciest parts of her book, including her drama with Glee co-star Lea Michele and her past engagement to Big Sean.

The 29-year-old actress became a household name in 2009 for her role as Santana Lopez on Glee, and she told us that at the time the show came around, she was at the end of her rope with her acting career. Despite past roles on The Bernie Mac Show and Soul Food, Rivera was ready to give up the Hollywood grind before striking gold with the Fox musical series.

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"I reached a point where I was like, 'I have to go to college and get a real job, because money matters, and this doesn't seem to be working out,'" Rivera tells ET. "My mom was the one that was like, 'Just give it 6 months and go on everything and don't be picky and just see what happens.'"

Rivera looks back fondly on Glee's early days, but admits that at some point her relationship with Michele started to reflect the tension their TV characters, Santana and Rachel, shared.

"Santana and Rachel hated each other, but they also had this love-hate sort of relationship, and I feel like Lea and I had that while we were on the show," she says.

Rivera adds that there were times when Michele was "unprofessional" on set, but says that it didn't always involve her.

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As Rivera practically grew up on television, fans watched her as she progressed professionally and romantically. In 2013, she got engaged to rapper Big Sean only to have the wedding called off in April 2014. Rivera says the breakup was made all the more painful, because she found out she wasn't engaged anymore through a press release.

Despite feeling blindsided, Rivera was able to take a lesson away from the failed relationship.

"I need something really genuine," she explains. "[I learned] what a genuine relationship is about."

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Now, Rivera is happily married to actor Ryan Dorsey with whom she shares an 11-month-old son, Josey. Rivera says she would like to have more kids in the future, but not any time soon.

"Momma's about to turn 30 and needs a couple more cocktails before we do that!" she says.