Yetta’s Yearning by Michele Lindsey

Now that his mine has paid out, Nathaniel can finally hang up his pickaxe and fulfill his dream of owning a cattle farm. He’s also looking forward to settling down and starting a family. But he’ll need a wife first.
Yetta has spent her whole life at the Wigg Foundling Home and School in New York City. First as a foundling herself, now as teacher, living in the dorms. Longing for adventure and yearning for a family of her own, she jumps at the chance to go west and start her own school. Turns out, becoming a mail-order bride is just the way to make it all happen.
It seems Yetta’s found everything she was looking for – a loving husband, a community in need of a school, and adventure to last a lifetime. But will the excitement be too much and send her back to the safety of the Wigg School?