When one has a close relative or friend let me call her Mandy that actually everybody knows lies a lot, one really does not know if Mandy lies to 80% or 20% but we as humans we want to be certain and sometimes think the worst so even though we care for and love Mandy we really do not want to give her big responsibilities where She can lie and cheat and swindle everybodys money and get away with it. If it ever happens something to her and her family then we can not help her because all the money is lost. So Mandy get´s her share when it is her time to get it. But no matter how much Mandy promise that She will be responsible to take care of the rest we do not really trust her before She has quit lying, threathening, and being aggressive if She does not get what She want, if She ever will.
Something Mandy could do is, saying She will do certain things She says She will do or that She and others has agreed upon, write it up, then do it, and write done, when it is done. Then all can see Mandy has stayed true to her word and it is a way out of breaking the evil circle.
Instead of lying, She could find out why She does lie, is it out of fear, because She want´s attention etc. Then if it is fear, do something that either overcomes that fear, get stronger, break bad relationships or build them better or communicate better...therapy. Attentionseeker, dress differently, maybe You had wrong colours, start excercize, get better posture, another haircut, go out and get some fresh air it will do You good, perhaps some new friends and remember to listen and count to 10 before You speak and then stop Yourself and think Do this sentence matter for eternity, does it truly build up the other person or is it only a lie puffed up with air. Try to see positive things in everybody around You, including Yourself, then there is no need for lying. And please, practice that smile atleast once a day, with Your eyes too preferrable in front of a mirror, That way You learn to laugh at Your self a little too. It is healthy actually. There are so many things in this world we can get upset about so we really need some rays of light too, practise to be light sometimes. If You smile, usually You are met with a smile. Then You need not feel insecure and take to a lie. So practise smiling.