There are many kinds of willow trees but the branches are always as thin as the emotions. If its a curlicue tree it symbolizes the emotional conflicts that prevent us from finding serenity. It will be very important to analyze the other elements of the dream to find the reasons of the conflict that bothers us. If its a weeping willow by association of the name it symbolizes sadness.
Read more about dreaming of Willow tree in other dream meanings interpretations.