Continue to listen. Then listen some more. Don't dwell on it. Encouraging trauma victims to relive their tragedies is central to all forms of crisis intervention. Most people would gladly forget about the assault if they could.
Most partners feel shame, rage, hurt, and powerlessness.
Just as victims need a supportive listener, their lovers also need a good listener to help sort out their reactions. This person should not be the victim. She already has her emotional hands full. Try a friend, family member or a professional counselor. Rage and shame are hard to work out alone.