LONDON (REUTERS) - Watch lots of television soaps if if you want to be happy, and don‘t even think of having an affair. After spending 11 years analysing thousands of questionnaires, Oxford Professor Michael Argyle believes he has found out what makes people happy. That the key was to have one close relationship and a network of friends. Marriage was one of the most important guarantees of happiness, especially for men, and the least happy in society were those who are divorced or separated, his research found. Extra-marital affairs brought unhappiness because of the damage they did to the marriage. He found that only the very poor were less happy and that those on middle incomes were just as happy as the very rich. Argyle found people were no happier — and no sadder — than they were 50 years ago. But he was surprised to find that TV soap addicts were a happy bunch. People who watch soap operas seem to gain a great deal of happiness from that. One theory is that through doing it, they are making imaginary friends.