Showing Light of My Heart by Ginny Aiken

Dr. Letitia Morgan comes to Hartville, Colorado, in the late 1800s to follow her God-given calling to heal. Soon she becomes Hartville's ministering angel, reaching out to the children of the town drunk, and skillfully touching all who need her.
But not everyone warms to the lovely new physician and Letty ruffles plenty of feathers when she takes on Hartville's thriving brothels. As she rescues first one then another young girl forced into the sordid trade, Letty becomes the target of some of the town's most powerful people.
Eric Wagner, Hartville's newspaper editor, finds he got much more than he bargained for when he brought this female doctor to town. As Letty stirs more controversy with each passing day, he wonders if he can save the noble-minded doctor from herself.
This is heart-warming and engaging fiction at its best, straight from the pen of a skilled storyteller.