Cece Wainwright's Christmas Wish - Wainwright Sisters, #3

Tropes: Grinch vs. Cindy Lou; Scarred, reclusive war hero; Epistolary; Widow; Forced Proximity Cece Wainwright married her childhood sweetheart and lost him at Balaclava six years ago. The only thing she has to remind her of him is the stack of letters he wrote her. And now there's a second stack sitting beside it - the ones she wrote him. They arrived via post three weeks ago from some remote Scottish hamlet. She wants to know who sent them and why.
Because she's suspected all along that her husband didn't pen those letters. Malcolm Buchanan fell in love with his best friend's wife through her correspondence. And his friend was ecstatic when Malcolm volunteered to answer her letters. He kept the letters after the war. Until he couldn't stand the sight of them because they reminded him of all the hopes and dreams he'd abandoned. Now she's standing on his doorstep demanding answers he's not ready to give.