To dream that you commit adultery or have an affair, is an expression of sexual urges or self-betrayal from your subconscious.

It also indicates that you will be entangled in a situation that is not in your best interest, perhaps even illegal.

To dream that your mate, spouse, or significant other is cheating on you, indicates your fears of being abandoned. You may feel some lack of attention in the relationship.

Alternatively, you may feel that you are not measuring up to the expectations of others.

To dream that you are committing adultery with your spouse's friend, denotes that you are feeling neglected by your spouse.