Seeing your girlfriend with another man in a dream is jealousy's theater, not evidence — in the West insecurity staging its worst case, in the East a bond's account showing a feared shortfall, in Ibn Sirin's careful method a dream that must never become an accusation.
Three readings
In Western psychology · Jungian
Infidelity dreams are among the most common relationship dreams and among the least predictive — they track the dreamer's insecurity, comparison anxiety, and felt distance, not the partner's behavior. The rival is usually a composite: whatever currently receives the attention you want. Waking anger at a partner for a dream is a well-documented trap; the honest use of the dream is as a gauge of your own security, and possibly a prompt to ask for reassurance plainly instead of collecting evidence.
The Eastern ledger reads this dream as fear of a shortfall in the bond's account: attention you feel migrating, a rival not necessarily human — her work, her circle, a season of distance — personified as a man because that is how jealousy draws. Classical counsel is stern about one thing: the dream is the dreamer's entry, not the partner's deed. Audit what has made the bond feel less secured lately, and address that; nothing else in the dream is actionable.
The tradition's ethics are unambiguous here: a dream is never proof against another person, and the ugly dream about an innocent is owed the ḥulm's treatment — dismissal, not narration. Read as meaning for the dreamer alone: the dream marks fear for the tie and perhaps the whisperings of jealousy, and its counsel is guarding the heart and the tongue — strengthen the bond openly, accuse no one on the night's testimony.
Vividness is not evidence. Every tradition and every study lands the same place: this dream measures your insecurity, not her conduct. Treat it as information about a fear, and bring the fear — not the accusation — to the conversation if it persists.
Why do I keep dreaming this after being cheated on before?
Old betrayal leaves a sentinel that patrols new relationships at night. The dream is the scar rehearsing, not the present repeating. Naming that history — to yourself and eventually to her — usually retires the sentinel faster than reassurance alone.
Should I tell my girlfriend about the dream?
Tell the feeling, not the film: 'I've been feeling insecure lately' opens a door; 'I dreamed you were with someone' hands her a trial she never attended. The traditions agree — the dream belongs to you, and so does the work it names.
This is the general reading. Your dream is specific.