The book -- "Rising Star: The Making of Barack Obama" written by David J Garrow -- shares for the first time the story of the woman Sheila Miyoshi Jager, his love interest, with whom Obama lived in Chicago, The Washington Post said in a review.
Jager tells author David Garrow, "In the winter of '86, when we visited my parents, he asked me to marry him."
Jager's parents objected to the union, believing her to be too young, as she was in her early 20s and two years younger than Obama, according to the review.
She was 23 and Obama was 25.
Their romance continued, but Jager says Obama's political ambitions got in the way. Possessed by a sense that he was destined to a life in politics, and could even become the first African-American president, she says race soon cast a shadow over their relationship.
"I remember very clearly when this transformation happened, and I remember very specifically that by 1987, about a year into our relationship, he already had his sights on becoming president," Jager told Garrow.
Obama eventually asked Jager to marry him again before he departed for Harvard Law School. He wanted her to go with him, she says, despite their increasingly fraught relationship, "mostly, I think, out of a sense of desperation over our eventual parting and not in any real faith in our future."
After his first year at Harvard, Obama returned to Chicago as a summer associate at a prestigious local law firm. There he met Michelle Robinson, the future first lady and an employee at the firm, the report said.
Their relationship quickly became serious, although he still saw Jager when she arrived at Harvard on a teaching fellowship.
"I always felt bad about it," Jager tells Garrow.
Eventually, Obama and Robinson got married in 1992.
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