She built her identity around being the guardian angel of one of the highest angels to exist. To her, protecting her charge comes first, second and third. However, that doesn't mean that she would risk her own life for nin. No, because while her charge is immortal, she is technically not. She has arranged for a way to prolong her ability to survive most otherwise deadly threats, but it's nowhere near as all-encompassing as that of her charge's.
She was assigned to protect the angel in the war against Lucifer. After Michael had cast him down, she didn't have much to do for that particular job and concentrated on being a soldier in Michael's army.
When her charge went missing, she was the one looking for nin the longest. She didn't give up, even when nins friends long had accepted nin as lost. And she succeeded in finding nin. That was the time, she formed her identity around being a guardian angel.
Now, that her charge is more or less secure once more, she has to re-learn what it means to be her own woman, her own angel outside of her job and the sole purpose of finding and caring for her charge. By now, she's an older angel, which clashes with how she sees herself.
Trying to connect with current times, she accepts to take the young angel Elelel under her wings and navigate with her through the military.