So Daniel Day Lewis has dumped you and married another. Deya, take my advice, says Sue Goodwin ...
Dear Deya, I offer you my full sympathy as you reel from the shock of discovering that Daniel Day Lewis, the man you believed to be your boyfriend, has just married another on the sly. Of course you knew of Danny-boy's appalling track record, including abandoning the seven-months pregnant Isabelle Adjani, but who could resist an actor's charm? Unfortunately, an actor's exit from your life will invariably be as dramatic as their entrance. Consider Sylvester Stallone, who reportedly chucked Jennifer Flavin via Courier, or Rik Mayall who, the tabloids claimed, hotfooted it from one girlfriend's bed to meet another at the registry office, or Dear Larry (Olivier) - every actor's role model - who didn't think twice about bringing his mistress Vivien Leigh to his wife's post-natal bedside to admire his first-born son.

Unable to control their lives and loves (actors refuse to be seen as the authors of their own script) actors swing dangerously from role to role, eternal victims of circumstance. I should know; I've been there.

After two years of "resting" my boyfriend was finally offered an audition. Although still unemployed, he returned elated. He had found a true kindred spirit in the actress paired with him to play the part of lovers. Vain to the last, he added that she had confessed her adoration of him. When she begged him to attend her first night in an out- of-town play I allowed him to go on the condition he return before midnight. The deadline rolled by and still no sign. I was woken at 7am by his tearful cry: "You have no idea how I've suffered." Explaining that he'd been the victim of a cruel ruse on her part which forced him to spend a night on the floor of her ghastly digs, he said he hadn't slept a wink for thinking about me. I reluctantly forgave him, only to learn several weeks later that he had finally landed a job decorating her flat and then her body. His outrage was great: "She deliberately got me drunk, she tricked me again". This time I showed him the door.

Two months of imploring calls followed, informing me that his sole purpose in life was to regain both my respect and the relationship. Meantime, it was quite by accident that I learned of his engagement to her. An invitation to the wedding duly arrived.

(Maybe I should be grateful for his tact. My friend Sarah was no sooner dumped by her actor boyfriend than he had sold his film script about their relationship. Having re-written history to cast himself as the hero of the piece, he proudly announced that he would be playing himself. His deluded self-indulgence knew no bounds - he offered Sarah a non-speaking bit part.)

I was actually rather pleased to see the back of my boyfriend for, as you will know, Deya, "going out" with an actor is a tragic affair. Trips to the cinema and the theatre became unbearable. Successful actors on stage or screen, particularly younger ones or those known to him at Rada, were talentless himbos apparently given the role simply to torment Mark in his state of "rest". The misery soon extended to TV, radio ... even ad-breaks were torment for it's every actors dream to land an ad, despite their protestations about their "artistic integrity".

Then there were the thespy get-togethers involving endless drunken reminiscences about drama school and rep-circuits complete with hideous songs and wild gesticulations. At least he seemed to be enjoying himself, I thought, until he began the paranoid rantings concerning his "friends" laughing at his lack of success. And how could I forget Gareth the agent, bane of my life, who on the rare occasions when he remembered Mark's existence, advised him to turn down the few roles he was offered on the grounds that they might typecast him? I longed for the day he might advise Mark to stick to his day job (if only he'd had one).

Seeking a professional's explanation to this eternal child syndrome I consulted Andrew Evans, shrink to over 300 stars. "Actors are not ordinary people," he said, "they are very vulnerable and have little control over their lives; they lead a very rich fantasy life, you see." According to Evans, this allows them to divide their lives into two compartments. In one sits wifey, who combines creativity and understanding. In the other lies life on the road, including the on-tour affairs, "understandable in the circumstances".

This helps to explain the final performance my friend Emma received from her actor boyfriend when she confronted him with his affair with a young usherette. "You are incapable of understanding my life," he shouted. In fact she understood it all too well and decided to have nothing more to do with it.

Dear Deya, do as I did and leave your congratulations on the happy couple's answering machine, adding how delighted your friends were by the news of the nuptials. Being an actor, Daniel will soon read what lies between the lines: "good riddance".

All names have been changed.