Why can someone lie?

Can I learn to tell lies? Can I treat my friend like she treats me. I'm a male and she's a female. Do I need to seek help and hide my business. Females see you lack security so they just expose it by lying. Sorry for being so vague. I give her money and see her everyday. I'll marry a pretty lady any day I just am of low income and give my heart to females and now this one is the one I pay and see everyday only to go for heart break or what. I don't think a female can be honest with me. Marriage takes me out the player game. I'll enjoy only playing with my wife.