What is the test for a restraining order against an unfaithful spouse?

In the final case, People v. Bridgehouse (1956) 47 Cal.2d 406, 303 P.2d 1018, the defendant's wife admitted to the defendant that she had been unfaithful and often discussed the affair with him. (Id. at pp. 407408, 303 P.2d 1018.) The defendant sought a restraining order to prevent her from associating with her lover in the presence of her and the defendant's young son. (Id. at pp. 408409, 303 P.2d 1018.) A few days later, the defendant shot and killed the lover when the defendant arrived at his mother-in-law's home with his son and unexpectedly came upon the lover, who was living there. (Id. at p. 409, 303 P.2d 1018.) The court concluded that these circumstances constituted "adequate provocation to provoke in the reasonable man such a heat of passion as would render an ordinary man of average disposition likely to act rashly or without due deliberation and reflection [citation]." (Id. at pp. 413414, 303 P.2d 1018.)