Well here' my .02 so take it with a grain of salt.
Tell her straight forward and honestly that you feel that she hasn't been honest with you and believe that you deserve the truth. Tell her that there were a few things that you've discovered, but are giving her the opportunity to talk to you.
She'll ask what have you found out, etc. But before she gets into that rant, hold up your hand and repeat again the above and that you deserve the truth. She could lie to you, but listen to what she says. And most importantly, do this calmly and not going off the handle.
After she's done, don't say anything. Just look at her calmly and say that you have alot to consider now. And then walk away.
Before jumping to the POTENTIAL OM's W, give your W the benefit of the doubt first.
M-43 W-40 2D - 9 and 5
Emotion, yet peace. Ignorance, yet knowledge. Passion, yet serenity. Chaos, yet harmony. Death, yet a new life.