Unquiet Land by Sharon Shinn
Leah Frothen has spent five years in self-imposed exile, recovering from a failed relationship and hating herself for abandoning her baby daughter. Now she's back in Welce, determined to find her place in society and learn to be a mother. When the regent asks her to spy on mysterious ambassadors from a visiting nation, Leah finds herself developing a dangerous friendship with an unscrupulous foreign woman and falling in love with a man she's not even sure she can trust. And soon she learns that everyone -- her regent, her lover, and even her daughter -- have secrets that could save the nation, but might very well break her heart. -- from author website.