What does it mean to dream about jealousy?
Jealousy in a dream usually points to something you fear losing or feel you lack, and the rival in the dream is often worth reading as a mirror rather than a fact.
Four ways to read it
Each reading below comes from a named tradition and a cited source, so you can see where it came from and decide what fits your dream.
Freud
Freud read jealousy as bound up with desire and rivalry that reach back to early family life. He held that the dream can revive an old competition for love and place. The feeling, in his account, often says as much about the dreamer's wishes as about any rival.
After Freud, The Interpretation of Dreams (Brill trans., 1913), public domain.Jung
Jung would see envy as pointing to something in another that the self has not yet claimed in itself. The admired or resented figure can carry a quality waiting to be developed. The feeling can mark a value the dreamer has set outside rather than within.
Jungian concept (our summary).Modern
Continuity research ties dream jealousy to waking insecurity in relationships and comparison with others. Some accounts suggest the sleeping mind works over threats to bonds we depend on. What the feeling fears losing is the thread worth following into waking life.
Continuity hypothesis (our summary).Mythological
The jealousy of Hera drove much of Greek myth, and envy among gods and mortals set many tragedies in motion. Some traditions personified envy as a wasting figure who could not bear another's good. The feeling was treated as a force that corroded the one who held it.
Rosmerta Publishing editorial synthesis (after Bulfinch; Brewer).