Your mother and sister can visit her. It is totally prohibited for you
to bring her or even to communicate with her before getting married,
let alone have your male members see her! Tell them that this is the
ruling of Allah, whether they like it or not!

Dear Sheikh, how do I explain to my parents that they cannot even see my future Wife until she is considered a mahram to my male family members eg Father and Brother? I was asked by my younger Sister and Mother to bring her home and introduce her to them as they also wanted to see how she looked like. She is a student of knowledge by the way.