Is it bad that I'm going to tell my roommate that her food and habits are triggering to my past eating disorder?
Are you sure you should say this? How will she react?
I think she will understand me.
It is good to point something out if it can cause harm. You should be kind when you tell her so she doesn't feel attacked.
She doesn't deserve me being nice to her.
You should be nice so you don't have awkwardness at home. Just talk it over and you both can come to an agreement.