Triangulation is where the narcissist brings a third person into the dynamic - perhaps another unwitting victim who is being groomed by the narcissist as a source of
narcissistic supply, or a hopeful fan who is flattered that the narcissist is shining their light on them.
This tactic invokes feelings of jealousy and insecurity in the victim, giving the narcissist a sense of power and sadistic enjoyment - all great
narcissistic supply.
You may have been triangulated with your narcissist’s work colleagues and subordinates, who would be casually dropped into conversation or messaged in front of you. Old flames may also be used for triangulation, and even members of the narcissist’s own family. A narcissist will also triangulate their spouse in couples therapy or mediation with the professional, getting them on side by playing the victim, playing them off against the true victim. Even a narcisisst’s children may be on the receiving end of these behaviours, and be triangulated with their cousins, other people’s children or with each other (“why can’t you be more like your sister?”)