To dream of ghosts typically represents the parts of you that cause you fear. This could deal with some difficult memory or repressed feelings. You could fear death or of dying. Ghosts in dreams can also signify something that you realize you cannot attain anymore, such as a dream that has died. It suggests that you feel cutoff from society in some way. This dream could be urging you to reevaluate the way you think and behave in order to move ahead in life.
To dream that you try to touch a ghost that vanishes suggests that you are working toward dealing with emotions or ideas that you've kept buried, even though you may not be ready to completely address them.
To dream about the ghost of a living relative indicates that someone may try to cause you harm.
To dream of the ghost of a dead friend or relative indicates that you have some shame about a relationship with that dead friend or relative.