Gaslighting is probably the most widely known of these terms and gets used frequently. It pops up in everyday conversation, with people jokingly accusing their friends of gaslighting them. Even my parents have now picked up on the phrase and it is thrown around in conversations at home.
Despite the lightness surrounding it now, gaslighting is actually a serious manipulation technique, commonly seen in abusive relationships where one party will try to convince the other that they are crazy, by creating a false narrative. This may include referencing things that haven't happened, minimising situations or emotions, and withholding information. It is a dangerous technique which can lead to the receiver feeling confused and unsure about their own sanity.
Negging refers to a subtle way of wearing down someone’s self-esteem. This can be via backhanded compliments, comparison to others, or insults under the guise of constructive criticism. The issue with negging is that the insults will never be obvious enough for the victim to actually be able to call the person out on it. Or if you do, they’ll play it off as a joke, acting as if the other person just being overly sensitive. They might even try and flip the narrative, acting upset at being accused, and playing the victim.
Triangulation is a term used in psychology that describes the use of a third party being brought into conflict between two individuals. This could manifest in a variety of ways. Perhaps the third person is being used to make one of the others jealous, or as a channel of communication between them. They might be forced into being a mediator, or act as a shield for one of the other people.
The problem with triangulation is the way that it ignores the root of the problem between the two, instead focusing on the conflict between them, which makes it much harder to solve. Although some people will use this technique deliberately to manipulate people, it can also happen accidentally when someone is shy, or afraid of conflict and therefore refuses to directly challenge the person that they have a problem with.
Although manipulation techniques are most commonly thought to happen in romantic relationships, they are just as common in other types of relationships, including friendships and families.