The new - last Sunday - SoCal women's Pro 123 crit champ is racing age 14 (I think she is 14).
So, although not as trained, or as experienced, she likely has an undeveloped engine near what the others do.
She should be aware if she is hurting - they are hurting.
In general women race much less aggressive. So the aggressive one that can suffer more benefits. I'd encourage her to forget winning and just go out and mix it up and attack, and attack. and if she blows up - no big deal.
I don't know N VA racing, but women's fields are often small in SoCal.