Helen Fielding - Why, when people are leaving their partners because they're having...

Why, when people are leaving their partners because they're having an affair with someone else, do they think it will seem better to pretend there is no one else involved? Do they think it will be less hurtful for their partners to think they just walked out because they couldn't stand them any more and then had the good fortune to meet some tall Omar Sharif-figure with a gentleman's handbag two weeks afterwards while the ex-partner is spending his evenings bursting into tears at the sight of the toothbrush mug? It's like those people who invent a lie as an excuse rather than the truth, even when the truth is better than the lie.