The Shattered Rose by Jo Beverley

When Galeran of Heywood returns from the Crusades, longing for his wife, Jehanne, he finds his castle under siege and his wife alone with a child that is not his own.
Seeing Galeran alive was all Jehanne ever hoped for. But credible rumors of Galeran’s death wrought dangerous folly that Jehanne never expected when they kissed goodbye three years prior.
Now enemies from church and state hover, looking for spoils, and Galeran and Jehanne must decide: find a way to forgive each other and fight together, or allow others to orchestrate their fate.