No! Don't ask her to compare you to this other guy. Believe that you are worth loving because you are. Can you take her somewhere where they can't call or text each other? Or maybe there is someplace she has always wanted to go where you can rekindle your relationship away from OM? If the moment is right invite her to talk and then listen with all your soul. If you listen she will tell you. Resist jumping in to defend yourself or explain etc. Just nod and listen. At the end tell her she is wonderful and thank her for sharing her thoughts with you. Ask her if she knows how beautiful she is to you. Act happy and confidant. Figure out things to do that you probably after all these years know she would like to do and plan them without her. Good luck.