(a) A proceeding to declare the nullity of a marriage may be instituted in the case of—
(1) an infant under the age of consent by such infant, through a next friend, or by the parents or guardian of such infant; or
(2) an idiot or lunatic by next friend.
(b) No proceeding to declare the nullity of a marriage may be instituted by a person who, being fully capable of contracting a marriage, has knowingly and willfully contracted any marriage declared illegal by sections 1 and 2 of this title.