Is My Sister A Pathological Liar?


One year ago my sister divorced her husband and ever since then she has been extremely unpredictable and lies constantly. She lies about things that really it doesn’t even make sense to lie about. For example, whether or not she’s at home, or what she’s doing that day.

She has a teenage daughter and has even driven her to the point of running away. She tells her daughter that her father does not care about her even though her father tries so hard to be in her life. She does not allow anyone in her daughter’s life anymore. I have no idea why this is. She even goes to the point of spreading rumors about our own father and mother about how our father sexually abused her as a child. However, she is in her 30’s now and does not even make sense to bring up at this point.


We know for a fact she is lying about that because we all know the real story. She also seems to have an obsession with trying to make everyone hate their fathers. She hates her own parents, though just last year she loved them, and now she is trying to make me hate my father (we have different fathers). She is also trying to make her daughter hate her father as well by telling her all these terrible things about him that aren’t true.

She has been constantly lying to everyone about anything she can ever since about a year ago when her and her husband divorced. It has come to the point where my family and I can’t help but think she must have some sort of mental disorder. Pathological lying disorder? I am not sure, please help.

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There is no way I can determine whether your sister is a pathological liar or has some other problem. However, what I do know is how families line up and take sides for or against someone. Yes, it does appear that your sister is going through a difficult time. The combination of divorce and raising a daughter who is a teenager is difficult to say the least. This may explain some of the behavior you are seeing. What I can’t help but ask myself is whethe or not you or other relatives have discussed these things with her along with expressing genuine concern for her.

In talking to her (if you have not already done so) it’s important to not be judgmental. Everyone, if they feel judged, become defensive and non communicative. My conern is that, judging from the tone of your email, has become critical of her.


In avoiding criticism it is really important that your sister’s claim that her father molested her not be dismissed. The fact that she is now 30 years old does not mean much. She may have harbored a secret up until now because she felt anxious or guilty about it. On the other hand, yes, she could be fabricating the whole thing. There is no way to know.

There is certainly a lot of emotion that has been aroused about your sister. For example, on the one hand you say that she hates her parents and on the other you report that she love her parents last year. Something here does not make sense.

As far as her daughter wanting to run away, you must be aware that there is a national problem with some teens who want to run away from home or those who do run away. The reasons for this are many and complex and one of the factors is drug abuse. Another is abuse. I have no idea if either is true of your niece only that, once again, everyone in the family should refrain from judgment.

Perhaps a family meeting and honest discussion would help? There are family therapists who help with this kind of thing and might be able to help all of you.

My intuition tells  me that there are many problems that lie within the family relationships and are not limited to any one person.

I hope this helps

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