The back story is fantastic in itself, a true story of Berloiz being so infatuated with ******* Smithson, a lady who refused his affections, that he poisoned himself by overdosing on opium. The symphony is his reenactment of the strange dreams that he had as a result of the opium. The premiere was in her honour but she didn't show up. However, she attended the sequel of Berloiz' symphony, realised both were about her, and agreed to meet with him and later married him. The marriage was short lived. He eventually moved on with a mistress of his own, and she died shortly.
The original 'entanglement'