A Match, Unmasked (Dukes Of War #8)
Erica Ridley

Now she’s a spinster of means, enjoying her freedom at the masquerade ball of the season. Kitty has forgotten that old foolish tendre. She has no need for Brigadier Baxter. Which is a good thing, since she hasn’t seen him in five long years.
But wait… who is the handsome man behind that mask?