The Wedding Day - Catherine Alliott

Annie O'Harran is the wrong side of thirty. A harassed single mother (of almost teen-aged Flora), she's escaped her faithless first husband with a few shreds of dignity intact, and against all expectations - met her hero: David Palmer is a kind and gentle doctor with a private practice in Belgravia, and Annie has a blissful summer ahead to plan their wedding.
But first Annie must escape the constant interruptions of her tiny Fulham house, and surround herself with calm in order to meet the horrible deadline set by the only publisher ever to have expressed interest in her writing. Giving mad Aunt-to-be Gertrude a cameo role in her novel is surely a small price to pay for the loan of a fabulous writer's retreat on a Cornish cliff with its own private beach?
No sooner has she arrived in Cornwall, however, than the doorbell starts ringing. Everyone, it seems, from her competitive sister Clare and her noisy brood, to her louche ex-husband Adam and his nubile young girlfriend, has had the same idea for their summer holidays. And then there's the houseguest who doesn't even bother to knock... Just as long as none of them affects her big day at the end of the summer...