We have similar issues.
Make it to where it isn't about place on the team in her mind.
Simply have it be where she is focused on growing effort throughout the race. Have her goal to be in mile 1 simply to stay calm and run her race - make it about how she feels and not where she is relative to others. This way she still has something to run for when things begin to get tough. She'll be in the right frame of mind.
Then the focus is on moving up and increasing effort. It is a task - not an outcome.
Late in the race it should be about running for others. This will make her leave her own pity party because the focus will be on helping teammates instead of her likely current egocentric view of position on team.
Btw - How did it turn out?
If you got through, you can try this next week. It has helped mine who were developmental athletes.