Bridget Jones's Diary by Helen Fielding (1996)

Chick keeps diary of alcohol use, weight gain, workplace drama, and romantic troubles. Loosely based on Pride & Prejudice. The book that started it all. Utterly hilarious and utterly re-readable. 

Followed by Bridget Jones: The Edge of Reason, based this time (even more loosely) on Austen's Persuasion. Noteworthy for the utterly hilarious scene in which Bridget Jones interviews the actor Colin Firth about his role as Mr. Darcy in Pride and Prejudice.

The Bad Seed by William March (1954)

Mrs. Penmark, left alone while her husband is away on business, begins to notice that her daughter Rhoda is not like other girls. Best know for its campy (but still chilling) movie adaptation, this well-crafted psychological horror novel is a worthy companion to Shirley Jackson's The House on Haunted Hill.

The Object of My Affection by Stephen McCauley (1987)

Endearing and funny tale of a complicated straight woman – gay man relationship. Stephen McCauley has a gift for great characters and complicated relationships, as well being blessed with a knack for a great turn of phrase. 

Other great McCauley novels are Alternatives to Sex and True Enough.

Atonement by Ian McEwan (2001)

Set in three time periods and surrounding an English family and their house in the country, this novel is filled with beautifully written meditations on writing and love. There was a lovely bit about how control freaks love to write, because they can have control over the events and people they write about. (McEwan put it more beautifully, of course.)

We Need to Talk About Kevin by Lionel Shriver (2003)

Written as a series of letters to her estranged husband, this is the story of a woman whose son grows up to be a school shooter. Fascinating exploration of what went so terribly wrong with Kevin--from the early days of her marriage to his childhood and beyond. Hypnotic and horrifying.