Girls, Why do women lie in relationships?

My wife and I have been together for almost 6 years now and I still catch her lying all the time we just moved and because she was busier at work and I was she asked me to clean out the different desk pack and unpack for my home office and hers found a book leave some sort of diary from before we were together where she clearly list different guys that she had sex with and things about the better relationship with a very odd way I say that to say she's always lied to me about the number of men she slept with and use the number about half of what I saw this notebook and the notebook leaves out me and her past two boyfriends who she lived with I'm as someone has had a very colorful past don't understand why she still has a lot of me about these things when they come up especially since she's usually the person who brings them up
Girls, Why do women lie in relationships?
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