All the contradictions of Allen's 25 crazy years unroll in real time. In 140 character chunks she debates what she should donate to Twitrelief, bemoans the cockroach in her room service spaghetti and urges her followers (there are 270,000 of them) not to watch the Channel 4 documentary about her latest venture, a vintage clothes store called Lucy in Disguise.
Not much heat about the pasta al arthropod but Allen's plea for a boycott of the show, called Riches To Rags, generated 697 news articles, in Australia, Canada and India as well as the UK and US. What might have slipped into the schedules and disappeared without much of a trace had become a story.
Allen thought she was signing up for "a show about sisters starting a business". (Lucy in Disguise is run with her older sibling, Sarah Owen.) She is unsure if she even got a fee. It was filmed in 2010, when Allen was pregnant for the second time. She had a miscarriage, also her second, in November, and shooting resumed after. On camera, she describes recovery as "a really long battle".
So far, so traumatic. But the show includes her having a go at Madonna and talking about her eating disorder. Now, by calling for a bodyswerve of the show, these unguarded remarks have attracted even more attention. "I used to vomit after meals," she said on camera. "It is not something I am proud of. But I tell you what, a lot of people used to come up to me and tell me how great I looked. And I was on the cover of every magazine with them saying, 'Lily is looking amazing - look how much weight she has lost'."
• Facts of Life: Lily Allen
It's a classic television trick: choose a gobby subject, get them off guard, press their buttons, stand back and wait for the controversy to start. And Allen, despite five years in the eye of the tabloid storm, falls for it every time. Lily Rose Beatrice Allen has been in and around the media all her life. She was born in Hammersmith in 1985, to film producer Alison Owen and actor Keith Allen. Her father left when she was four, leaving Owen to bring up Lily, Sarah and their little brother, Alfie, in a council flat. Her childhood vacillated between poverty, privilege and rock'n'roll excess: American rock musician Angela McCluskey is her godmother, she called Clash frontman Joe Strummer "Uncle Joe"; she was in and out of 13 different private schools and expelled from several for drinking and smoking. Summers meant Glastonbury, she had walk-on parts in The Comic Strip Presents ... (co-written by her father) and Elizabeth (co-produced by her mother). Harry Enfield was, for a while, her stepfather.She has, as Wikipedia notes wearily, "a number of half-siblings".
Allen's musical talent was spotted when, aged 11, music student Rachel Santesso heard her singing Wonderwall in the school playground. Santesso, now a singer and producer, gave her lunchtime singing lessons and coached her first public performance: Baby Be Mine, from Disney's Dumbo, at the school concert. Allen also played piano, violin, trumpet and sang in a chamber choir.
She left school at 15, unwilling to "spend a third of my life preparing to work for the next third of my life, to set herself up with a pension for the next third of my life". Allen sold Ecstasy in Ibiza and began training as a florist, all while hawking herself round different record labels. Finally, in 2005, Regal Recordings, home to Coldplay and Gorillaz, gave her 25,000 to make an album. She recorded demos of Smile, LDN and handful of others. Regal planned to release them as an album in 2007. Allen, an impetuous teenager, was having none of it. She posted the songs on a newfangled website called MySpace, which rapper Lady Sovereign had told her about in the pub. With one click of the "download now" button, Allen became one of the first stars to short-circuit the label system and use the internet to find her own audience. As her "friends" on the site grew, it took over her life. "My concentration was really bad because I was interested in going home and reading about how much people love me on MySpace," she told one journalist. "I wasn't even thinking about writing any new songs. Instead I'd read all the messages, Oh you love me! Great! Great!"
Eventually, with the input of producers Greg Kurstin and Mark Ronson, Alright, Still was released in July 2006. It sold and sold. The single Smile was a hit in the US and UK, all helped by the fact that Allen's MySpace blog provided journalists with a drip feed of juicy stories.
Allen announced she was pregnant by her then boyfriend, Ed Simons of the Chemical Brothers, in December 2006. She miscarried a month later. The relationship ended, much vodka was spilled, nightclubs were fallen out of and Allen spent three weeks in a psychiatric clinic dealing with the aftermath.
A second album, It's Not Me, It's You, released in 2009, is clearly the work of a more mature - although still cheeky and irreverent - Allen. It sold massively and spawned hit singles It's Not Fair and The Fear. The same year she began seeing builder Sam Cooper. Allen announced she was pregnant the next August, during the filming of Riches To Rags, with the baby due early in 2011. She miscarried three months later, days after being photographed on the red carpet, showing off her bump.
Allen claims she is not giving up on motherhood and plans to try for another baby, after she and Cooper marry this summer.Meanwhile she is busy discussing her wedding dress with Karl Lagerfeld - she has become something of a muse for the Chanel designer - running her own record label (funded by Sony), writing the music for the stage show of Bridget Jones's Diary, discussing a job on The X Factor judging panel. She closed her MySpace account in 2009 and has no plans to record any more music or play live. For the time being. Allen is still a work in progress and mass of contradictions, always prone to changing her mind. "You know, it's really complicated," she told one confused journalist. "I've got a funny little brain. I'm still trying to figure it out myself."