In a food processor or blender, combine cranberries, 1 cup sugar, crushed pineapple, and walnuts. Pulse until coarsely chopped without becoming mushy. Cover and refrigerate for an hour to let the flavors blend.

In a medium bowl add the cream cheese 1/2 cup sugar and beat until smooth. Add the heavy whipping cream and continue to beat with the cream cheese until stiff peaks form. Fold the cranberries and marshmallows into the salad. Cover and refrigerate for at least 3-4 hours or overnight.