(a) In cases where the parties to an action commenced under the provisions of this article have not executed a separation agreement, or have executed an agreement which is incomplete or insufficient to resolve the outstanding issues between the parties, or where the court finds the separation agreement of the parties not to be fair and reasonable or clear and unambiguous, the court shall proceed to resolve the issues outstanding between the parties.
(b) The court shall consider the following factors in determining the amount and duration of spousal support and separate maintenance, if any, to be ordered under the provisions of parts V and VI, §48-5-1 et seq. of this code as a supplement to or in lieu of the separation agreement:
(1) The length of time the parties were married;