One Sweet Moment by Maggie Craig

It's 1822 and Scotland's capital is a city of both splendour and squalor. Kate Dunbar is worked like a slave all day and preyed upon at night in the gloomy vaults that lurk under the Old Town's South Bridge but never gives up hope of a better life for herself and her beloved young brother Andrew.
When wealthy young medical student Richard Hope walks into her life, Kate knows that his interest in her could lead them both into danger. Yet it's not long before the two of them have fallen head-over-heels in love.
Others are watching the young lovers. Radical booksellers Peggy and Nathaniel Henderson have Kate and Andrew's best interests at heart. Their greedy and grasping uncle doesn't, and he soon soon starts laying his own evil plans.
Kate and Richard's passionate and poignant romance intertwines with the richly-imagined colour and pageantry of King George IV's historic visit to Edinburgh in 1822, and culminates in the heart-stopping drama of the Great Fire of Edinburgh of 1824.
Can their love affair have a happy ending or will fate, the evil that threatens them and the rigid rules of class and society allow them only one sweet moment of happiness? From Goodreads.

This is a very sad romance. I like the main character Kate a lot, she does what it takes to survive and care for her brother. Her uncle and aunt are awful but there are good people around. Richard, a wealthy medical student, finds out how the poor of Edinburgh live and finds love. Do not reed this if you only like books with a happy ending.

This book qualifies for:
2014 Ebook challenge
Read Scotland 2014
Meet the Protagonist Reading Challenge 2014
CCC A-Z Book Titles 2014
You Read How Many Books? Reading Challenge 2014
The Challenge Factory Spell It Out - Supercalifragilisticexpialidocious (O)
Romance Readers Reading Challenges: 2014 Chubby Chunkster (452 pages)
Crazy Challenge Connection - Dr. Seuss
Goodreads Reading Challenge 2014
Nothing but Reading Challenges - Spell it Out - Animal Alphabet (O-coyote)