A Tangled Web: Allan's Miscellany 1846 (Allan's Miscellany #3)
Sandra Schwab

Her whole life Sarah Browne has been told how plain she is, how nondescript, destined to become an old maid. For years she has been her family's dutiful nursing maid, but now a secret inheritance and an encounter with the charming Mr. Pelham seem to offer her a chance to break out of her life of duty and drudgery - if she dares to take it. Yet how could such an interesting, witty man be possibly interested in her boring self?
And so, Sarah soon find herself entangled in a web of lies and deceit, which might even cost her the love of her life.