4. They’ll try to make you jealous.
Healthy relationships thrive on security; unhealthy ones are filled with provocation, uncertainty and infidelity. Narcissists like to manufacture love triangles and bring in the opinions of others to validate their point of view. They do this to an excessive extent in order to play puppeteer to your emotions.
In the bestselling book Psychopath Free by Jackson MacKenzie, the method of triangulation is discussed as a popular way the narcissist maintains control over your emotions. Triangulation consists of bringing the presence of another person into the dynamic of the relationship, whether it be an ex-lover, a current mistress, a relative, or a complete stranger.