Well, she embraces Selune fully after House of grief fight, no?
Also fun fact
when you enter shadowlands for the first time - you get dialogue with Shadowheart how curse doesn't work on her and Shar loves her.
However, if you try to enter deep shadow zone(where you need pixie lantern/blessing bascially) - she still has no protection against it. Her "protection" basically mimics Isobel's blessing of Selune that allows you to walk around, but not in the deep shadows. Wouldn't Shar give her full protection from that, because it's her curse? Maybe it was Selune all along, that protected her.