First, if you are not on the same page with your trainer - i.e. why is she starving herself. This is not a good sign and you do not want a trainer telling you to do stupid things!

Yes, you can get hurt sometimes when training even with a trainer, but your trainer, should listen to you if you really don't want to do somethings. This is a fine line however, because your trainer may need to you to things you really don't want to do but things that will not hurt you. So be careful with this.