Naya Rivera's new book Sorry Not Sorry dropped yesterday (Sept. 13) and in it, she shares details from the final days of her relationship with Big Sean which include catching the rapper cheating with Ariana Grande. Sean was engaged to Rivera un until April of 2014, and started Grande shortly after, the two musicians lasting for about eight months. Grande is now dating another rapper, Mac Miller, but as Rivera tells it, she discovered the singer getting pretty cozy in her then finace's house.

"We'd been fighting for five straight days while he was traveling, and then on the one day that he was back in L.A., he said he didn't want to see me,” Rivera writes in her memoir “‘Well, asshole, I've got a key to your house,'...I walk in, go downstairs, and guess what little girl is sitting cross-legged on the couch listening to music? … It rhymes with ‘Smariana Schmande.’”

What's more, Rivera shares that she learned of her split from Sean not from the rapper herself but via the news, writing, “I learned that I was no longer getting married from the internet, and at the same time as the rest of the world... Not only were we no longer getting married, but apparently we weren’t even together anymore.”

Around the time of their split, Sean released "IDFWU" what is believed to be a celebration of his break-up, such lines as "And everyday I wake up celebration’ shit, why? / Cause I just dodged a bullet from a crazy bitch." Based on Rivera's take though, it sounds as Sean did less dodging and more ghosting.

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