Willow

Willow by Linda Lael Miller. paperback edition. ISBN: 9780671706319.

Montana was a wide-open, lawless land when the golden-haired Willow married Gideon -- a railroad magnate turned U.S. Marshal. Their union was tempestuous and passionate, a mating of two fiery, strong-willed souls destined for each other. But Willows love for her husband was matched by her devotion to her outlaw brother, a renegade pursued by a man sworn to hunt him down -- Gideon! Willow had to choose....She could betray her own kin, or risk everything -- even the love she had dreamed of all her life -- to save him.