Dealing with knowing and not saying anything

[Daz_Con]

I have only posted in the newcomers section, for the full story here is my sitch..
My sitch
My WAW has not admitted anything to me, if I have ever asked about her boss being over all of the time she only says he is just my friend and is helping me. Even after I have found him over there at 10AM on a Sunday. I recently found love letters from him to her. This pretty much seals it if there is an PA, but its slightly possible that he is just chasing her hard, he gave her 30K to help her move out!!. She might have an obligation she fells to hang with him since he helped her so much. She has said to me "he may have somthing in the back of his mind for more" In the cards it was all love stuff, hopeful and waiting to see what the future holds etc.. not friend stuff. I have not said anything to her about it, just moved on allot, have gotten more of a life, lots of friends and the like, and giving her space now, I need to move on more and work on my being healthy emotionally for myself and kids

Also my D12 and S11 found them (cards), and read them, just last Sunday. So it is pretty obvious to everyone except W. Kids want to confront her, I will try to discourage that.

My question is how do I handle knowing and still DBing? I havent called her, only when necessary, when she calls I am very friendly and all, stay in good mood during any contact, have just elected to let it run its course. Last night she called 3 times, I did not answer, called her back this AM. Not typically me, before coming here I would have thrown them in her face and told her it was over. But I want to save my M and family, this is my second marriage, and very important to me not to have my older ones go through a second breakup.

I find my self thinking of it allot though, the lying is what gets me the most, why does she not just admit it? I practice mindful thinking, just does not work much.