Can a psychotherapist/patient privilege be waived when a patient voluntarily discloses otherwise confidential information?

Of course the psychotherapist-patient privilege may be waived when the patient voluntarily discloses otherwise confidential information or tenders her mental state as an issue. (See Evid. Code, 912, subd. (a), 1016; Roberts v. Superior Court (1973) 9 Cal.3d 330, 340.) However, "[t]he waiver of an important right must be a voluntary and knowing act done with sufficient awareness of the relevant circumstances and likely consequences." (Roberts v. Superior Court, supra, 9 Cal.3d at p. 343, italics added).