Depending on the severity of deception I have multiple ways to deal with it. I will always confront without emotion and leave her extremely insecure on how I feel about it. If it's a white lie I'll ask her why she felt the need to lie to me about it, in a way that conveys I have a bigger issue with lies than what she actually did. This will indirectly tell her that whatever wrong she does will get worse if she decides to lie. White lies are dumb lies, it's the things she think I would have a problem with that really doesn't matter much.
There's the greater lies, the type of lie that she knows she should tell me or the type that would cause problems. I will make her feel anxiety, ask her if she did what I already know she did. The important part is that I must know to a high degree of certainty what she did. If she comes clean I'll give her another chance, but I'll clearly state I'm not an idiot and I won't tolerate lies. This WILL increase her anxiety if she considers lying again, she'll remember my stone cold attitude about it. If she does lie again I'll dump her and say I warned her, I will reject all attempts at trying to get me back.
The worst lies are the ones that will really hurt me, now we're talking cheating or anything directly related to the relationship. Again I gotta have my facts straight, there's gotta be no room for plausible doubt. I will still confront, I might (doubtfully) give her a chance if she goes through the extreme discomfort of being honest to keep me. The first sign of denial or rationalization and the conversation along with the relationship is immediately over. I'll casually say "I know what you did", she is bound get a spike in anxiety because she will know exactly what I'm referring to. If she realizes she's screwed and comes clean I will question a lot. Why she did it, how she did it, why she didn't just leave me, if she thinks I'm an idiot, if she considered how she made me feel, if it would be ok if I did it to her and finally if she loves me at all. Basically the very hard questions and she has to be brutally honest, and I'll make it clear she's not gonna be able to bullsh!t her way through them. If she shows absolute humility, remorse and understanding of how wrong it was then MAYBE I'll offer another chance. If I do I'll make it abundantly clear if she ever does it again she's dead to me, if she does then I'll stick to my words.
In any case I know how to make people very very uncomfortable if they lie to me. Even if I'm never going to see them again I'll do it for the sake of saving someone else the pain, to make one less liar.
