In Virginia, the court must take into account a number of factors in an award of alimony follows below:

20-107.1. Court may decree as to maintenance and support of spouses

"...D. In addition to or in lieu of an award pursuant to subsection C, the court may reserve the right of a party to receive support in the future. In any case in which the right to support is so reserved, there shall be a rebuttable presumption that the reservation will continue for a period equal to 50 percent of the length of time between the date of the marriage and the date of separation. Once granted, the duration of such a reservation shall not be subject to modification."