It does good to no woman to be flattered [by a man] who does not intend to marry her; and it is madness in all women to let a secret love kindle within them, which, if unreturned and unknown, must devour the life that feeds it; and, if discovered and responded to, must lead, ignis-fatuus-like, into miry wilds whence there is no extrication.

Jane Eyre An authoritative text (ed. 2000) - ISBN: 9780393103236