We often talk about “gaslighting” in connection with a manipulative behavior used by a narcissist in dealing with their victim. The term originated in a 1930’s play called Gas Light, in which the main character is attempting to make his wife believe she is going crazy by dimming the lights ever so slightly each day, and convincing her it is all in her head. It was later made into a movie starring Charles Boyer and Ingrid Bergman which emphasized the way male privilege is used to gain power over women.
Today, the term gaslighting is used in connection with domestic violence, coercive control and emotional abuse, most often perpetrated by a man over a woman who might be his girlfriend, his wife, or his live-in partner. The term has become part of mainstream culture and refers to various types of subtle psychological manipulation. Below we will talk about what it is exactly and why it is dangerous, and what the forms of gaslighting are. 
It is hard to identify gaslighting because it happens in non-obvious ways, yet it insidiously makes the victim doubt herself and her own perceptions. Some examples are:
• Denial – the perpetrator (the gaslighter) constantly denies statements he’s made or actions he performed, even when they clearly did happen.
• Blame shifting – the abuser blames the victim for any problems that occur, never taking responsibility for the things that he causes.
• Minimizing – the abuser constantly minimizes emotions and thoughts of the victim to the extent that her feelings are invalidated or she buys into words such as “you are irrational” or “you don’t know what you are talking about.”
• Manipulating Reality – The gaslighter distorts the truth, making the victim doubt her memories and perceptions.
• Isolating – The perpetrator keeps the victim away from friends and family so that she has no support system left and can only rely on him.
As you can imagine, the long-term effects of gaslighting can be severe. The victim begins to doubt her own experiences, feels confused, has less and less confidence in her own beliefs, and can develop anxiety and depression from the relentless manipulation of the gaslighter. The continuing and profound psychological manipulation can even make the victim doubt her own memories of physical or verbal abuse. Not every gaslighter uses physical abuse but many allow the victim so little freedom financially, physically or socially, that the victim doesn’t know who she is anymore, except in relation to the abuser.
Gaslighting is a powerful form of psychological abuse that can cause lasting damage. There are steps you can take, up to and including making an exit plan. If you think that you are a victim of gaslighting, get professional help to restore your faith in yourself and your perceptions.