The valley in a dream represents our feelings of inadequacy, need for change, and the feeling that we cannot overcome our problems. It also represents the obstacles that we face when trying to reach our goals. The valley can also represent an issue or need that needs to be resolved or overcome in order to move on with life.
A common remedy for when seeing a valley in your dream is to overcome it with finding something positive in our lives, achieving something meaningful and/or finding someone who can help us through our troubles.