Heaven did not seem to be my home; and I broke my heart with weeping to come back to earth; and the angels were so angry that they flung me out into the middle of the heath on the top of Wuthering Heights; where I woke sobbing for joy. That will do to explain my secret, as well as the other. I’ve no more business to marry Edgar Linton than I have to be in heaven; and if the wicked man in there had not brought Heathcliff so low I shouldn’t have thought of it. It would degrade me to marry Heathcliff now; so he shall never know how I love him; and that not because he’s handsome, Nelly, but because he’s more myself than I am. Whatever our souls are made of, his and mine are the same, and Linton’s is as different as a moonbeam from lightning, or frost from fire…

… I cannot express it; but surely you and everybody have a notion that there is, or should be an existence of yours beyond you. What were the use of creation if I were entirely contained here? My great miseries in this world have been Heathcliff’s miseries, and I watched and felt each from the beginning; my great thought in living is himself. If all else perished, and he remained, I should still continue to be; and all else remained, and he were annihilated, the universe would turn to a mighty stranger; I should not seem a part of it. My love for Linton is like the foliage in the woods. Time will change it, I’m well aware, as winter changes the trees — my love for Heathcliff resembles the eternal rocks beneath — a source of little visible delight, but necessary. Nelly, I am Heathcliff — he’s always, always in my mind — not as a pleasure, any more than I am always a pleasure to myself — but as my own being — so, don’t talk of our separation again — it is impracticable.
~ Catherine Earnshaw (Ch. IX).

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Wuthering Heights is the only published novel by Emily Brontë, written between October 1845 and June 1846 and published in July of the following year. It was not printed until December 1847 under the pseudonym Ellis Bell, after the success of her sister Charlotte Brontë’s novel Jane Eyre. A posthumous second edition was edited by Charlotte in 1850.