Still life

I've just finished Still Life by A. S. Byatt and I think I'm in shock. Towards the end of this brilliant novel she delivers such an unexpected, sudden broadside to the plot that it has left me quite literally breath-taken. In order not to spoil the book for anyone else who wishes to read it I shall say no more on the exact circumstances and events. However, yet again I am astounded at the effect a novel, a world of people conjured out of the author's life and imagination, can have on a reader, who never meets any of this people, or enters into this world, except through the author's words. The reader never learns anything of this world and its people than what the author tells them and his or her knowledge is based on what the author chooses, consciously (and sub-consciously, some would argue) to tell the readers. Yet the people live and are passed from one imagination to another, to the extent that, over my reading of this and the previous work in the canon, the world she portrays currently feels more real than the world in which I live. I long to ask her, the author, the god of this paper universe, "why???" Why like that? It is incredible the effect a mere story can have.