The Baby Bombshell (Shadow Creek, Montana Book 2) by Victoria James

Lily Cookson has a few rules for the New Year, the most important being don't fall for Jack Bailey. The gorgeous, rugged man returned with a new look and a determination to win her back, catching her off guard. After a forbidden night in his arms, she vows never to let it happen again. But when morning sickness kicks in a few weeks later, Lily realizes staying away from Jack just got a whole lot harder.

Jack Bailey left Shadow Creek behind five years ago when his world imploded around him, knowing it would be best for everyone if he was gone...including Lily. It took him a long time to get his life back on track and grow into the kind of man she needs him to be. Now he's determined to prove to Lily that he's back for good and ready to commit, but the secrets she's holding onto are nothing compared to the bombshell he drops...