Hi hun, it depends what we mean by having a normal life. I haven't start refeeding yet but I'm confident that if I follow the refeed carefully that I will maintain my new life and have the occasional drink/meal out etc.
I can never go back to my previous lifestyle or I will definitely put it all back on. Did your friend do the refeed properly and is she careful about what she is eating? Not being personal about your friend but however we lose the weight, if we go back to old habits we will put weight back on. Maintainence is a whole new process of learning.
Also is there a mistake on your ticker or is your BMI really at 19.1? If it is then that seems pretty low if you don't mind me saying and I think anybody would struggle to maintan a super low body weight. Sorry if that seems a bit cheeky x