Every insurer providing coverage for hospital or medical treatment and for the treatment of mental, emotional, nervous, or substance use disorders or conditions shall ensure that the financial requirements applicable to such mental, emotional, nervous, or substance use disorder or condition benefits are no more restrictive than the predominant financial requirements applied to substantially all hospital and medical benefits covered by the policy and that there are no separate cost-sharing requirements that are applicable only with respect to mental, emotional, nervous, or substance use disorder or condition benefits; and the treatment limitations applicable to such mental, emotional, nervous, or substance use disorder or condition benefits are no more restrictive than the predominant treatment limitations applied to substantially all hospital and medical benefits covered by the policy and that there are no separate treatment limitations that are applicable only with respect to mental, emotional, nervous, or substance use disorder or condition benefits.