Connie Booth has a simple explanation for why she lost her enthusiasm for sitcoms. The actress and co-writer of Fawlty Towers once said: "I used to watch a lot of comedy until I got divorced. Then I went off it."

The American-born actress - whose status as a creator of the show voted the greatest in British television history has often been overlooked - endeared herself to millions as Polly, the sensible but harried waitress who was the comic foil to the insanity of Basil Fawlty, played by John Cleese, her husband at the time.

But when their marriage began to unravel just as the couple were writing the second series of Fawlty Towers in 1978, Booth began to go off other things as well.

Not least among those was acting itself and the media spotlight that followed her every move, resulting in one of the more perplexing changes of heart in recent showbusiness history.

She has maintained a steadfast silence about Fawlty Towers - and the rest of an acting career that included a formative role in the Monty Python show - for at least 20 years and has not acted since 1995.

Booth's decision to eschew any and all publicity about the work of comic genius that made her - and the rest of the Fawlty Towers cast - famous the world over was resurrected yesterday when it emerged that not even the emollient questioning of the former Today programme presenter Sue MacGregor would persuade her to change her mind.

Producers of BBC Radio 4's The Reunion, which has reunited key players in events from the bombing of the Rainbow Warrior to the making of the first test-tube baby, wanted to gather the key members of the sitcom's cast to reminisce about the chemistry which made it such a success.

But while Cleese agreed to take part, along with Prunella Scales, who played Basil's hand-bagging wife Sybil, and Andrew Sachs, who played the hapless Spanish waiter Manuel, Booth maintained her refusal to have anything more to do with the show.

David Prest, the producer of the Radio 4 series, presented by MacGregor, said: "We had most of the Fawlty Towers cast lined up but Connie simply didn't want to have anything to do with it. We felt that as we didn't have everybody on board we had to abandon the idea."

Were there any doubt about Booth's withdrawal from public life, or at least from her media pigeon hole as the shapely ex-wife of a Monty Python who once stripped to her underwear on screen, the emphatic refusal of her theatrical agent to pass on any interview requests is further proof. As one former colleague put it: "She's put the show behind her. She's a very private person now."

Private, maybe. But Booth, now 63, is very far from a hermit living off the royalties that Fawlty Towers still earns 32 years after it was first broadcast. And the reality is that Booth, at least partially as a result of the experience of her divorce from Cleese, has achieved the Pythonesque feat of doing something completely different.

Since 2000, she has been working as apsychotherapist in north London, where she has been involved with a project helping single mothers.

She continues to guard her privacy jealously. Her last known interview three years ago with a local newspaper resulted in a complaint to the Press Complaints Commission when it stated that "like many an actor before her, she had found solace in therapy".

Booth complained that it gave a misleading impression of her as needing therapy but the PCC rejected the complaint, saying the paper had made it clear she was a professional practitioner rather than a patient.

For many, Booth's desire to protect her integrity by removing the baggage of her comedic past is entirely understandable, although not shared by that other performer turned mental health professional, Pamela Stephenson, who is currently starring in her own series of interviews with fellow celebrities.

But ironically, the roots of Booth's second life lie firmly within her first. It was during the break-up of her marriage to Cleese, an intense relationship by any standards, that Booth suggested they might both benefit from therapy.

The couple, who had a young daughter, Cynthia, at the time they were writing Fawlty Towers between 1975 and 1978, were separated when they began writing the second series and yet still managed to work together under Cleese's exacting requirements.

Speaking soon after the marriage ended in divorce in the autumn 1978, Booth said: "There had been difficulties for some time in the marriage, which is why we went for counselling. If it hadn't been for group therapy, I don't think we could have worked on the second series."

Although neither Cleese nor Booth has offered any insight to the reasons for the break-up beyond the fact that no one else was involved, the crucible-like atmosphere in which Fawlty Towers was created was a significant contributory factor.

In a recent interview, Cleese said: "Each episode took me and Connie six weeks to write and a week to rehearse and record. Before every recording, which was on a Sunday, I'd work all day Saturday to make sure the timing and the words were as good as possible.

"I had a perfectionist streak and I got terribly wound up over things. Writing Fawlty Towers meant going over everything again and again until we got it right. That attitude contributed to our break-up."

Cleese met Booth in the late 1960s while he was working the comedy circuit in New York. He was a Cambridge graduate in the early stages of a promising but as yet low-level performing career.

She was the daughter of a Wall Street magnate and a actress who had moved to New York state after Connie was born in rural Indiana. With her mother's encouragement, Booth began an acting career and was balancing jobs as a Broadway understudy and a waitress when she met her future husband.

Cleese said: "I went into a restaurant where all the waitresses were great-looking out-of-work actresses. Connie was one of them.

"With Connie, I had at last met someone who could express themselves as I would like to have done. It was instant attraction. But the tensions that took over during the making of Fawlty Towers struck a killer blow."

The couple, who married in 1968, got the idea for Fawlty Towers while working in Britain with the Monty Python team.

They stayed at the Gleneagles Hotel in Torquay where the owner, a former naval officer, made it clear he cared little for the foibles of his guests, throwing out those who complained until he was locked in his private apartment by his domineering wife.

Cleese hinted that both he and Booth, the first of his three wives, recognised a fiery side to their own temperaments. It is one of the ironies of the couple's subsequent and separate lives that Cleese is now married to a American psychotherapist, Alyce Faye Eichelberger. He is still friends with Booth and the couple both attended the marriage of Cynthia in 1995.

Cleese said: "Connie and I have always had a thing about people who can't suppress their rage, which neither of us can. There was a certain part of me in Basil... and, I suppose, a certain part of Connie too."

For her part, Booth has spoken only of the demonstrative nature of her upbringing. The rows between her parents were so loud that at times police were called by concerned neighbours.

She said: "My family was given to affection and anger and it was expressed with less restraint than in England. You could easily get smacked or spanked."

When the first six episodes of Fawlty Towers were broadcast on BBC2 in 1975, it was slated by critics and largely ignored. But when it was repeated on BBC1 the next year, it was a huge hit, attracting 12 million viewers and became a comedy classic.

Cleese's career continued on its upward trajectory thereafter but Booth's stuttered as she fell out of love with the glamour and clamour of showbusiness.

Despite a critically acclaimed role as the schizophrenic daughter of an abusive father in The Story of Ruth in 1981, the flow of roles on stage and on screen that appealed to her began to dry up.

By the time she took on a part in the 1992 British film Leon The Pig Farmer, Booth was beginning to work as a volunteer at a specialist mental health unit in Richmond, south-west London. She began her professional training as a psychotherapist in 1994 and qualified six years later.

Her personal life included brief relationships with the actor Anton Rogers and playboy Justin de Villeneuve before she met John Lahr, theatre critic of The New Yorker magazine and son of Bert Lahr, who played the cowardly lion in the classic film The Wizard of Oz.

The couple were together for 15 years before they married in 2000 and now live in Highgate, north London.

Whether Booth has now recovered her liking for comedy or ever watches the frequent repeats of Fawlty Towers may be for ever kept out of the public domain.

Instead, she seems to have taken away something else from her experience of playing Polly, the student and chambermaid who made a virtue of untangling the problems of others, and emerging from her marriage as a single mother in a foreign land.

In her only interview about her new role working with single mothers, she said: "I think a lot of these mothers suffered from being quite isolated.

"We can all feel that we are not doing a good job as a parent, we can sometimes feel ashamed. It's a real learning curve. I think things being aired and discovered are crucial."

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