In Norton v. MacFarlane, 818 P.2d 8, 15 (Utah 1991) the Court imposed a standard of clear and convincing evidence in alienation of affections cases and a requirement of proof that the conduct of defendant constitute the "controlling cause" of the alienation of affections. "'Defendant's conduct must have outweighed the combined effect of all other causes, including the conduct of the plaintiff spouse and the alienated spouse.'" Id.