For purposes of the Advance Mental Health Care Directives Act:

(1) Activation means the point at which an advance mental health care directive is used as the basis for decisionmaking as provided in section 30-4409;

(2) Attorney in fact means an individual designated under a power of attorney for health care to make mental health care decisions for a principal;

(3)(a) Capacity means having both (i) the ability to understand and appreciate the nature and consequences of mental health care decisions, including the benefits and risks of each, and alternatives to any proposed mental health treatment, and to reach an informed decision, and (ii) the ability to communicate in any manner such mental health care decision.

(b) An individual's capacity is evaluated in relation to the demands of a particular mental health care decision;

(4) Principal means an individual who is nineteen years of age or older with capacity who provides instructions, preferences, or both instructions and preferences for any foreseeable mental health care in an advance mental health care directive; and

(5) Relative means the spouse, child, parent, sibling, grandchild, or grandparent, by blood, marriage, or adoption, of an individual.