To dream of feeling grief, or grieving someone who is lost,, refers to your inability to let go of the past. You need to clear away your feelings about those old experiences and make way for the new.
To dream that you are wearing black clothing for mourning, symbolizes grief, bad luck, and unhappiness.
To see others wearing mourning clothes in your dream, signifies disturbing influences and misunderstandings among your friends.
Also see “Death.”