But here's the age-defying good news. For anyone who's a fan of the quirky, independent, fashion-forward woman Woody Allen directed to an Oscar — for essentially playing herself in 1977's Annie Hall, his ode to their relationship — Keaton is still just as quirky, independent and fashion-forward with a résumé that includes director, photographer and mother.  Now add author to that list. Three years in the writing, Then Again (Random House, $26), on sale Tuesday, is a quilt of reflections whose main purpose is to allow Keaton to explore her relationship with "the love of my life."  That's not Woody or Warren or Al, though there are poignant if polite mentions of high-profile beaus Allen, Beatty and Pacino. For Keaton, that love was her mother, Dorothy, who died in 2008 at age 86 after suffering from Alzheimer's disease for more than a decade. (Her father died of a brain tumor in 1990.)  Those hunting for Hollywood dish won't find it in this gossip-free reminiscence. But for anyone looking to join one woman's — albeit a famous woman's — touching and funny journey into the vortex that is the parent-child relationship, Then Again features an especially honest tour guide.  "My mother kept many journals (which are excerpted at length in Then Again), and reading them wasn't easy because sometimes you just don't want to go back there," says Keaton, curled up on a couch in a lounge of the Beverly Wilshire hotel, where, many moons, ago she'd rendezvous with Beatty in his penthouse.  "I had to go through my own journals, too, since the mission of the book was always to go back and forth from her thoughts about life to mine during a similar time frame," says Keaton, suddenly scrunching up her face. "I'd be reading my old stuff going, 'Oh, my God, you've got to be kidding, I've heard it all already, do you have to repeat yourself so much, you're driving me crazy.' "  Then a laugh, part sigh, part guffaw, and all Keaton. Ditto with the way she punctuates her speech, that oh-so-Annie Hall patois that includes liberal doses of "Oh, yes, well, oh, OK, yeah." Take this reflection on becoming an adoptive mother at age 50 to daughter Dexter, now 16, and son Duke, 10.  "In some ways, it's fortunate for them I am the age I am. In other ways, it's not so fortunate for them." Pause. "OK, but in other ways, it's fortunate for them, well maaay-be, that I'm past my 30s, when I was going out and was a big star." Pause. "Well, no matter how you cut it, I'm a parent now, so, well, yeah …" Silence.  That kooky self-examination is partnered with her charmingly zany look: black bolero pants, big black leather jacket cinched at the waist with a wide black belt, black-and-white striped shirt, wire-rimmed glasses — an updated iteration of the tie-and-hat look that made her a style icon years back.  Most moviegoers associate Keaton with her dominant 1970s star turns, which include roles as Allen's foil, Pacino's wife in The Godfather movies and Beatty's love interest in Reds.  But the truth is she has never been far from the camera in every decade since, whether in front of it (notably in comedies such as The First Wives' Club and Something's Gotta Give) or behind (directing features, such as Unstrung Heroes, and documentaries alike). Next year, she'll hit theaters in Lawrence Kasdan's Darling Companion and star opposite Robert De Niro in The Wedding.  Mom had her own dreams  This is not a woman who needed to write a book. She's someone who had to.  "I feel like I got to know (Mom) better doing this project," she says.  Would Dorothy have liked Then Again?  "I hope so. I mean, I think so," says Keaton, who in the book describes the difficult years helping care for her mother as her mind slipped away. "But I edited it, not her. I'm sure she'd go, 'Diane, what did you do?' " Big laugh. "Or maybe. I don't know."  As the memoir makes clear, Dorothy Keaton was, in a sense, a prisoner of her times. After marrying Jack Hall, a civil engineer, she settled into her very 1950s role as wife and mother. She was even crowned Mrs. Highland Park (Calif.) and had dashed aspirations of representing the greater Los Angeles area with her homemaking skills.  But at the same time, "my mother was an artist who didn't have the opportunity to have a craft. That wasn't in the cards for her," Keaton says. "She had dreams, but mainly she tried to make our dreams come true."  Then Again stars both Keatons. Together, their joint reflections give the memoir a three-dimensional depth, a distinguishing advantage considering the reams of Baby Boomer tell-alls flooding the market.  "Maybe it's our reality-TV age, but every (celebrity) seems to want to tell their story, even though only some really have stories to tell," says Mark Rotella, senior editor at Publishers Weekly.  "Few memoirs truly elevate the genre. Patti Smith did so with her book (Just Kids) about her times with Robert Mapplethorpe, and so did Tina Fey, using her humor to really reveal herself (in Bossypants)," he says. "It seems Keaton also is trying something really unique in terms of telling us about her life."  Keaton had the collage-like structure of the memoir "locked in early, even down to the way the book would look physically," says David Ebershoff, her editor at Random House.  His job was to keep his first-time author pumping out the pages, which Keaton did not do in chronological order but as the spirit moved her. Occasionally, Ebershoff had to remind her that what she might find mundane, readers would not.  "We asked for something about the night she won her Oscar. She said her memories were not complete and didn't feel it was that interesting," he says with a laugh. "We assured her anything she could remember would be great."  The result: "At the time it didn't dawn on me how inappropriate I looked in my 'la de da' layered getup, set against the backdrop of gorgeous women in spectacular gowns," Keaton writes. "Out of the corner of my eye, I spotted Jane Fonda. Oh, my God. Who was I kidding?"  In some stars, self-deprecation is a convenient facade to mask a huge ego. In Keaton, such raw honesty seems like the real thing. In fact, Then Again's true revelation is that during Keaton's rise to fame, she was being dragged down by bulimia.  "Writing about this now was just an opportunity for me to say, yeah, I'm No. 25 of the thousands who went through this. It kind of demystifies the investment I made in it," she says.  "No one really cares. But it's me owning that experience. It was a horrible time. It's grotesque and gluttonous. But you've created this wall and your whole life implodes into the rituals and insanity of performing this act over and over."  She attributes her descent into bulimia partly to being unprepared for her newly independent life in New York in her 20s.  "My mother did everything for me as a kid, from making the clothes I dreamed up to listening to my sad stories," she says. "My life was structured. So when I went off on my own, I didn't know how to handle it."  Her savior was comedian Allen, who shared her neurotic nature, inspired her with his work ethic, and eventually encouraged her to see a therapist. Though Keaton declines to talk in depth about the famous men in her life (she has never married), the mere mention of Allen's name — more so than Beatty's or Pacino's — brings a bright smile to her face.  "Woody helped give me a structure in terms of how to manage life, so that even today I like a lot of activities so I won't get depressed," she says, noting that the two still speak often. Allen famously is obsessed with death; Keaton counters with her own concerns about cancer and Alzheimer's.  "Oh, yeah, I think about every single ailment, like, oh, my leg, I can't feel it, what's going on?" she says, throwing her head back and laughing. "It's a darn Woody story, huh? Um-hmm. We were good together, two idiots going, 'Are you OK?' "  As much as Keaton revisits the past in Then Again, part of the book's unstated mission is to enlighten her future: Dex and Duke. Calling the former "beautiful and a mystery," and the latter "tiny, fast and smart, and a big capitalist at an early age," Keaton hopes her memoir will give her children insights into what made their grandmother and mother tick.  Then again, mere mention of her kids also can summon a pained look. It is a look of a mother contemplating the eventual departure of her kids, as did, some 40 years ago, Dorothy Hall.  "My mother wrote about that in her journals, you know. Being left. The emptiness." Keaton sinks into the leather cushions and wraps her arms around her knees. "It's a universal thing for all parents. You have to let them go, but it's hard. Because then, who are you?"
Diane Keaton has written a memoir that is as much about her relationship with her mother as it is a reflection on her famous life.