That is a tough break- not really much you can do running wise, other than intensive water running, if she wanted. A complete break to R&R and be ready to come back strong may sound good to her. In terms of positive thinking, things like this have happened to elite runners, too, and they have come back from it.
http://www.mensracing.com/athletes/interviews/dathanritzenhein03.htmlDathan Ritzenhein is one I know who struggled with femur stress fractures, which I imagine has similar recovery time.