“Oh come on. I never said that.”

“You’re just being overly sensitive.”

“I don’t know why you’re making such a big deal out of this…”

Psychologists use the term “gaslighting” to refer to a specific type of manipulation where the manipulator is trying to get someone else (or a group of people) to question their own reality, memory or perceptions. And it’s always a serious problem, according to psychologists.

“It is always dangerous,” Robin Stern, PhD, Associate Director of the Yale Center for Emotional Intelligence and author of "The Gaslight Effect," tells NBC News BETTER. “The danger of letting go of your reality is pretty extreme.”

It may start out with seemingly small offenses. But the problem is that even more-or-less insignificant instances of you questioning your own judgment or reality — thanks to the deliberate intent of someone else — can snowball. You can end up in a cycle of not being able to negotiate your daily life in a way where you are clear minded, can focus, can make sound decisions, and have a sense of well-being, Stern says.

Gaslighting happens in personal relationships (think an abusive spouse or, in rarer cases, parent), in professional relationships (a manipulative boss or coworker preying on a subordinate), and even by public figures. There are several examples of gaslighting being done by President Donald Trump and his administration, Stern notes.

No matter whether it’s happening in a marriage, between a leader and his or her constituency or elsewhere, it’s important to be aware of the red flags that you (or someone you know) might be a victim — which is the first step to getting out of the abusive situation.

Gaslighting usually happens in a power dynamic, but it’s not always intentional or malicious

There usually tends to be a power dynamic when gaslighting happens, Stern explains. The manipulator holds enough power that “the target of the gaslighting is terrified to change up [the relationship] or step out of the gaslighting dynamic because the threat of losing that relationship — or the threat of being seen as less than who you want to be seen as to them — is quite a threat,” she says

If it’s happening by someone you love and care about (like a spouse or parent), you’re going to WANT to believe the other person — and the gaslighter may use that against you, explains Darlene Lancer, JD, MFT, a marriage and family practice therapist in private practice and author of "Codependency for Dummies and Conquering Shame and Codependency: 8 Steps to Freeing the True You."

“Many people [in this case the targets of gaslighting] change their perceptions in order to avoid having a conflict,” Lancer explains.

But, the gaslighter doesn’t necessarily need to be acting with malicious intent — nor does the gaslighter necessarily need to realize that she or he is gaslighting another person for it to be happening, Stern says.

It might be a result of how you were raised. Maybe your parents had very cut-and-dry beliefs and that certainty is how they (and now you) see the world and when someone sees things differently you assume something is wrong with them, Stern says.

Maybe you’re upset because you think your boyfriend is always flirting with other girls. What you don’t see is that it’s the girls that are flirting with him and he’s just being polite. But your worldview doesn’t allow you to question that maybe you’re getting the situation wrong. You make him think you know way more about relationships and there’s something wrong with him that he’s not able to see the “error” in his ways.

“Maybe at first you don’t believe it, but over time you may come think that maybe she is right,” Stern says.

Be wary of gaslighting if you start to question yourself a lot

Recognizing that you or someone you care about might be in a “gaslight tango” is not always as straightforward as it might seem because it can start in very subtle ways — and often involves two people (or groups of people) who would otherwise seem to care about one another very much, Stern says.

The term “gaslighting” actually comes from a 1938 play, “Gas Light” (which was turned into a more widely known movie in 1944, “Gaslight”), where a husband manipulates his wife to make her think she’s actually losing her sense of reality so he can commit her to a mental institution and steal her inheritance. “Not all real-life examples are so diabolical,” Stern says.

A subtler example might be a mother always disapproving of her daughter’s decisions to the extent that the daughter questions decisions she suspects her mother would not agree with. The mother may or may not consciously want to control her daughter’s every decision, but by being overly critical she’s doing so.

Gaslighting can be when a popular high school student causes another student to question his or her feelings, or judgment of a situation. When that latter student asks the more popular student why the popular student didn’t save a seat at the lunch table, the popular student deflects the question: “Why are you being so sensitive? It’s not that big of a deal. I didn’t realize you didn’t have a seat.”

How gaslighting happens

According to the National Domestic Violence Hotline’s fact sheet, the techniques a gaslighter might use to manipulate someone else can include:

Withholding (meaning he or she refuses to listen or says they don’t understand)

(meaning he or she refuses to listen or says they don’t understand) Countering (when the abuser questions the gaslightee’s memory of an event)

(when the abuser questions the gaslightee’s memory of an event) Blocking/diverting (when the abuser changes the subject or questions the victim’s thinking)

(when the abuser changes the subject or questions the victim’s thinking) Trivializing (making the victim’s needs or feelings seem unimportant)

(making the victim’s needs or feelings seem unimportant) Forgetting/denial (when the manipulator pretends to have forgotten what actually happened or denies something he or she had previously agreed to)

And note that a gaslighter will oftentimes start with something that is true that you might be particularly sensitive about to hook you. A coworker, for example, who tries to convince you that you’re not pulling your weight in the office might bring up the fact that you complain all the time about menopause making you feel lousy. You may be feeling lousy because you’re going through menopause (and that coworker may have heard you complaining about it once or twice), but that doesn’t necessarily mean that your performance is changing because of it, Stern explains.

Signs you're a victim of gaslighting

According to Stern, look for these warning signs and red flags the type of abuse might be happening to you (or someone you know):

You’re constantly second guessing yourself or have trouble making decisions;

You’re ruminating about a perceived character flaw (like being too sensitive or not a good enough person);

You feel confused about your relationship (if you find yourself thinking: “I thought I had this great husband, but I just feel crazy all the time” or “I thought I had this charming partner, but then sometimes I feel like I’m losing it when we’re together”);

In a confrontation with the person that might be gaslighting you, you feel like you suddenly find yourself in an argument you didn’t intend to have, you’re not making progress or you’re saying the same thing over and over again and not being heard;

You feel fuzzy or unclear about your thoughts, feelings, or beliefs;

You’re always apologizing;

You’re frequently making excuses for your partner’s behavior;

You can’t understand why you’re not happy in your own life; or

You know something is wrong, but you just don’t know what.

What to do if someone is gaslighting you

And finally, what do you do if you do recognize that someone is gaslighting you? Here’s what Stern suggests:

Identify the problem. Recognizing the problem is the first step, Stern says. “Once something has a name you can being to address it specifically and granularly,” she says. (Sometimes writing down specifics from a conversation that you can look back to later — when you’re out of the heat of the moment — can be helpful in sorting out the truth from distortion, Stern suggests.) Give yourself permission to feel what you feel. Part of the problem with gaslighting is that it results in the victim questioning his or her own thoughts, values, perceptions or feelings. Acknowledge that what you feel is what you feel so that you can take whatever action you need to take to feel better. Give yourself permission to make a sacrifice. Part of what makes it tough for a victim to leave a gaslight tango is that the abuser is someone they care about, they look up to, or they have a relationship with. “You may have a lot of wonderful things going on in that relationship,” Stern says — but it’s not worth it if it’s undermining your reality. And to start to regain your sense of self that you’ve lost, you may need to cut that person off, give up some of those wonderful things, or live with that person not having such a high opinion of you, she says. Start with making small decisions. To get out of or to stop a gaslight, take one step at a time, Stern says. Say no. Don’t engage in an argument that’s clearly a power struggle. Get a second opinion. Ask a friend or family member you trust if they think your thinking is as off as your potential abuser says it is. Have compassion for YOU. “Having compassion for yourself is super important,” Stern says. You’re responsible to you. You need to be honest with yourself, Stern notes. Maybe tomorrow your partner will be great, but focus on what you’re feeling in the moment, she says. Recognize when you have those feelings: “Right now this feels like sh-t. He’s driving me crazy.”

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