Adele has made no bones about the fact that her first two albums were inspired by heartbreak, but she's refrained from airing much of her dirty laundry in public. So naturally, when writer Marc Shapiro decided to pen the superstar singer's unauthorized biography, he went digging for dirt -- and his new book, 'Adele: The Biography,' purports to tell the story of the shattered relationship that preceded her debut LP.

Shapiro, whose previous credits include a book about Justin Bieber, alleges that teenage Adele was hung up on a bisexual friend who may not have been totally forthright with her. The UK's Daily Mail reprinted an excerpt from the chapter in question, which reads: "Adele had professed her love and he did the same, she had known he was bisexual but, in the rush of romance, felt they could make it work ... Four hours after laying their emotional cards on the table, the boy ran off with one of Adele's gay friends!"

The rough outline of Shapiro's story is borne out by previous comments made by Adele, who told fans that the song 'Daydreamer' is "about this boy I was in love with, like proper in love with, he was bi and I couldn’t deal with that. All the things I wanted from my boyfriend, he was never going to be, I get really jealous anyway, so I couldn’t fight with girls and boys."