Too Long a Stranger (Women of the West #9) by Janette Oke

The sudden death of her husband had left Sarah Perry and her baby Rebecca alone in their small frontier town. But Sarah resolves for Rebecca's sake to put her life back together and go on. And to everyone's surprise, Sarah finds a way. But the choices forced upon her by life on the frontier are very hard. The most difficult decision comes when Sarah determines that the best thing for her little daughter's future is to send her away to boarding school.