Wuthering Heights review-2nd in the TBRP

Why is this book considered a classis.  I guess ‘classic’ is a subjective term.  I certainly wouldn’t call this book a classis.  Pride and Prejudice by Jane Austen is a classic, Moby Dick is a classic, Wuthering Heights?  Is it a classic because it’s dark and brooding and set in the moors?  Is it a classic because of the love story?  I didn’t see a love story.  Heathcliff was a bully and Cathy was crazy! 
Did I enjoy the book?  No, I can’t say that I did.  I liked that the narrator was the housekeeper and that at the end the young Cathy and Heathcliff are nicer to each other.  It’s crossed of my list of books to read!