(a) Every health care agency may be revoked by the principal at any time, without regard to the principal's mental or physical condition, by any of the following methods:

(1) By being obliterated, burned, torn, or otherwise destroyed or defaced in a manner indicating an intention to revoke;

(2) By a written revocation of the agency signed and dated by the principal or by a person acting at the direction of the principal; or

(3) By an oral or any other expression of the intent to revoke the agency in the presence of a witness 18 years of age or older who, within 30 days of the expression of such intent, signs and dates a writing confirming that such expression of intent was made.

(b) Unless the health care agency expressly provides otherwise, if, after executing a health care agency, the principal marries, such marriage shall revoke the designation of a person other than the principal's spouse as the principal's agent to make health care decisions for the principal; and if, after executing a health care agency, the principal's marriage is dissolved or annulled, such dissolution or annulment shall revoke the principal's former spouse as the principal's agent to make health care decisions for the principal.

(c) A health care agency which survives disability, incapacity, or incompetency shall not be revoked solely by the appointment of a guardian or receiver for the principal. Absent an order of the probate court or superior court having jurisdiction directing a guardian of the person to exercise the powers of the principal under a health care agency that survives disability, incapacity, or incompetency, the guardian of the person has no power, duty, or liability with respect to any health care matters covered by the agency; provided, however, that no order usurping the authority of an agent known to the proposed guardian shall be entered unless there is notice to said agent by first class mail to the agent's last known address and it is shown by clear and convincing evidence that the agent is acting in a manner inconsistent with the power of attorney.

(d) A health care agency may be amended at any time by a written amendment executed in accordance with the provisions of subsection (a) of Code Section 31-36-5.

(e) Any person, other than the agent, to whom a revocation or amendment of a health care agency is communicated or delivered shall make all reasonable efforts to inform the agent of that fact as promptly as possible.