Matter of Trust by P.O.Dixon
The Shades of Pemberley
Another P.O. Dixon what if, and again an excellent read.
It's full of deviations and twists and turns, these turn the original story of Pride and Prejudice around and send it off in a completely new direction.
This variation has Darcy being told by his Father on his death bed that George Wickham is a Darcy. But, he dies before he can explain how they are related. Darcy thinks the worst, that they are probably half brothers which is why he has kept bailing George out and kept scandal from his door.
We also have the return to Pemberley of Alexandra, younger sister to Darcy's father who has been out of the country for twenty plus years and has some big chips on her shoulders. She moves back into Pemberley and is determined to be the mistress of the house and rides rough shod over the newly wed Elizabeth Darcy.
Darcy and Elizabeth have married hastily after an incident with Wickham at the Netherfield Ball causes Mr Darcy to guard Elizabeths honor by announcing their engagement.
As you can imagine this changes the plot in so many ways......
I will say no more of the plot as you need to read this book for yourself and find out what happens to poor Lizzy. Now she has Lady Catherine and Lady Alexandra looking down their very aristocratic noses at her.