Rebirth by Jordan Silver

Gabriel Russo had been born under a dark cloud. He knew his history like the back of his hand; his mother made sure of that. He knew what blood ran through his veins and what it meant. He also knew that there were some with that same blood who would kill him if they could.
Born the product of a horrible act inflicted upon his mother by one of the Ricci brothers, now the adopted son of another very powerful family, he’s the heir to two of the most powerful Familias in the West.
No one knows what this young man whose life was marked even before birth would do to survive. And when they finally do, it’s usually too late. There’s only one woman who can tame this volatile young man, and when he sends her away after high school for her safety, he loses what little humanity he had left.