Personally I would confront her. Not in an accusing way, but in a way that's understanding and compassionate. In fact, you do have a right to know in case you contract some kind of STD.
If you don't, she may flip back to the guy if he changes his mind and also, she can't keep blaming you for the demise of the relationship.
Again, be compassionate when talking it over with her. If she starts to switch the blame to you and say that you're crazy, etc. hold up your and stop her. Tell her that you have proof and would like to get past it, but you need to have complete honesty and trust between the two of you. Watch your tone when you're doing this.
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.
