Section 7. Voidable marriages

A marriage is void from the time its nullity
  is declared by  a  court  of  competent  jurisdiction  if  either  party
  thereto:
    1.  Is  under  the  age  of  legal  consent,  which is eighteen years,
  provided that such nonage shall not of  itself  constitute  an  absolute
  right  to the annulment of such marriage, but such annulment shall be in
  the discretion of the court which shall take into consideration all  the
  facts and circumstances surrounding such marriage;
    2. Is incapable of consenting to a marriage for want of understanding;
    3.  Is  incapable  of  entering  into  the married state from physical
  cause;
    4. Consent to such marriage by reason of force, duress or fraud;
    5. Has been incurably mentally ill for a period of five years or more.