In the meantime, tell her you don't believe that you're such a great guy and that everything is all right with the relationship.
If it had been all right, she wouldn't have ended it! Tell her that she may think that silence is protecting your feelings, but you would rather hear everything that 's she's keeping in her heart, most especially her negative feelings.
Tell her you want to know what you did to drive her away. This should open the door for her to talk honestly. When she shares her real feelings with you, listen and understand.
Point out to her that she has a tendency to hide her feelings and get fed up and walk out. Tell her that no relationship can survive this type of pattern. Tell her that if she runs from you, she won't get far because her problem will haunt her in the next relationship.
So why not stay with you, who loves her, and work on resolving her pattern of silence. Tell her that you want her to come back and commit to telling you every day what is good and what isn't good about your life, what you've said and done, etc.
I want to hear what happens.