The Whispers Between Us By Cynthia Bastuck

Charlotte Fairmont knows her duty — save her family from ruin by marrying well, regardless of her heart’s desires. The engagement is expected, the wedding planned and her future sealed. But when she overhears her intended threatening everything her family has left, she has no choice but to fight back. And no one to turn to but a stranger with clever eyes and too many secrets. He shouldn’t be her ally. He certainly shouldn’t be anything more.
But he makes her feel what no proper suitor ever has:
A flutter. A yearning. A dangerous hope that could cost her everything she holds dear.

Stephen Turner has spent years invisible — standing against the walls of the ton, serving their needs, watching their games from a distance. He knows better than to want what he cannot have. He has always known better. But when Charlotte Fairmont stumbles into his path, desperate and cornered, he offers his help before good sense can stop him. And suspects it never could have.
Because her mere presence awakens something in him:
A recklessness. A hunger. A forbidden dream he would risk everything for.