The West Indian narrator vents her bitterness at the unhappy life fate dealt her--mother died in childbirth, father ignored her, stepmother tried to kill her, at school she had an abortion. Finally, she married a white doctor, but it was impossible for her to love him because he was a colonialist. She draws parallels with the despair of her country--Dominica--attributing it to the legacy of slavery. By the author of Lucy.
This doesn't mean that this book's narrator is particularly likeable, or that the book is particularly enjoyable. Kincaid wrestles with a lot of painful history here, but isn't aiming at any particular reconciliation. Her depiction of the Caribbean is, like V.S. Naipaul's, spare and pitiless, and, while Kincaid's description of the act of physical love are marvelously vivid,, there isn't a lot of love or fellow feeling to go around here. A lot of the book's social and personal chasms remain unbridged. Not to put too fine a point on it, but this is the sort of book that's more or less guaranteed to make a lot of well-intentioned white people feel decidedly uncomfortable. This, of course might be part of it's concept, and that's fine. But potential readers should keep in mind that it's probably easier to admire "Autobiography of my Mother" than it is to enjoy it.
Her father is a distant and venal man, and Xuela doesn't think much of him. By necessity, she is essentially on her own. However, as the book progresses, she seeks something(?) in others: the narrator has an affair with a much older man, marries a white man who cares deeply for her but whom she does not love, and falls in love with a married man to whom she is only one of many women.
Xuela strives to find an identity and a place for herself in the world, but through all her striving is a dark fatalism which undercuts her: what she describes as a 'bleak, black wind' at her back. This can be read as stemming from her family situation, her community, her gender, and the legacy of colonialism - but it's also simply and matter-of-factly portrayed as just the way this character is, without apologies or excuses.
Is this actually Kincaid's reconstruction of her mother's life, or is the title a reference to the looming absence of the narrator's mother? I'm not sure.