You don't need to worry about triggering therapists, they have ways to deal with that in supervision etc.

It's hard for anyone to be looked at and judged by another, because of weight, gender, clothes, disability, race etc.

How you look at other people and judge them speaks volumes about you, it says nothing about the person you are looking at. It must be very useful for her to have these behaviours show in therapy, so it can be addressed.