Sharpshooter in Petticoats (Sophie's Daughters #3)
Mary Connealy

Tom Linscott is fed up with waiting for Mandy who should have had the sense to come to him as soon as she finished burying her worthless husband. In fact he'd've come fast enough to dig the hole if she'd've sent for him. He goes to round up his little woman and buys into a heap of trouble from a whole clan of outlaws.
Between Mandy's deadly skill with her rifle, her determination to not bring trouble down on someone she loves, and an ever growing crowd of varmints who want to bury everyone named Grey—and anyone who sides with them, Tom may not survive getting himself hitched.