IT had to happen. A movie about internet romances. Tom Hanks and Meg Ryan star in a film to be released next week, You've Got Mail, the story of two people who surf into love online, to use the net's own particular brand of jargon.

The film, a romantic comedy, set in New York's Upper West side tells the tale of two people who, in the real world, despise each other but who find themselves attracted when they meet anonymously on the Internet. Far fetched? Not at all.

Web surfers have pen names, not real ones. You have no idea whether they are telling the truth or not. There is no way of checking. The woman who says she is divorced with three kids could have a decent husband working all hours to pay her phone bills. The man who talks of his separation from the wife from hell, could be making the whole thing up. The poor woman could be ironing his shirts in the next room while he furtively chats to Mizz Libra from sunny California. On the Internet you can be all things to all people and there are no limits.

America online, one of the largest Internet providers, is hoping that You've Got Mail will introduce greater numbers of people to their ''Buddy Chat'' lines and perhaps the film will serve its purpose. But it is very important not to ignore the dangers.

Of course, there are those who strike it lucky. One woman bought a ticket to see her ''buddy'' 600 miles away and hit it off immediately. My own husband chatted for months to women in different parts of America. He longed for the American dream, got it in the shape of a sweet-talking opportunist from Philadelphia and was off.

Internet chatting can become the most terrible addiction. In the US it is big business for psychiatrists and seems to be catching on here pretty quickly. It is estimated nearly half of all Internet users become addicts and, believe me, it is not an easy obsession to live with. Because of the changes in time zones there is ''chatting'' late into the night or early morning to allow for the time differences on both the east and west coasts.

Helen Petrie of Hertfordshire University is author of a report which states that there is genuine threat to the family with chat addiction. Many of those she interviewed preferred to be online than being part of the home environment. The whole concept gave the addict a buzz, a feeling of excitement not experienced elsewhere.

Her research showed that the first thing many do when they come home from work is make for the computer to start communications or to find out if there are any e-mails which America Online's disembodied electronic voice announces with the words ''You've got mail'', as in the film.

Kimberly Young, a professor of psychology at America's University of Pittsburgh, has found there to be even more sinister traits brought to the surface by serious addiction. Lying to family or friends about the amount of time spent on the Web, restlessness, inability to concentrate, neglect of children, and anxiety when not engaged in computer activities are often noted.

''Pathological internet use'', as the affliction is called, has spawned a number of support groups in the US. One of them, run by Maressa Hecht Orzack, a psychologist at Harvard University's McLean Hospital, receives hundreds of pleas for help each year, often from families broken into pieces by online affairs which have led to divorce.

Of course, this kind of fantasy link-up attracts the vulnerable and does most damage. Those who feel insecure or are going through a bad patch in their lives can find consolation and be good prey for the faceless creatures on the other side of the Atlantic where sugar-coated psychologist advice is given out by the wagon-load.

''My wife is cold and uncaring,'' says Allybee, which may be only one of his web names. ''Oh, no. You don't have to put up with that. You're meant for better things. Get peace, get rid of her,'' comes the soft-soaping claptrap from the women of America to net a soft touch.

Often, if the Web relationship becomes serious, deviousness takes over. Presents are secretly sent, telephoning begins on the quiet when even more heartache is poured out and even better saccharine-filled platitudes offered, this time with real contact. The comes the finale. One day you find your husband or wife has followed the American dream trail and will be with you no longer. Sounds unreal? It happens, and to lose your partner to the nastier aspects of the Internet is not a happy business.

Not long ago a man came to sit beside me in the hair salon. He was nearly 60 and told the stylist he was a civil engineer, about to retire. ''I'm getting married soon. She's from the States but I haven't been over there yet,'' he said. ''One of those internet romances. They're happening all the time now.'' Let's hope he isn't in for a shock. Had I heard that conversation a year ago I would have paid little attention thinking it was one of those things that happened to other people, certainly not to my family.

But there you are. Life is full of surprises and certainly can be full of very unpleasant ones of you find your ''buddy'' is not the person you thought them to be. Even when Mizz Libra or Allybee reveal their true identity to each other there is still no way of knowing if their CVs are bona fide. Here the biggest danger lies and it's the easiest thing, as the Americans would say, to be ''conned big time''. And many have.

The Internet is, of course, full of marvellous uses for all sorts of reasons and, indeed, it can be a friend to those who live in isolated parts of the country and have little social contact. As always, it's the bogus minority that spoils it - the men and women who manipulate the truth about their circumstances and leave families in tatters as a result.

You've Got Mail may be a comedy for some, but an unhappy reminder of reality for others. It is one film I shall certainly skip.