that is the General's young wife (they weren't able to really be together i think, they had only been betrothed before the General had to go suppress the southwestern war). she was tasked with a mission by the General's great aunt (Qu Chen and Ah-ting's grandmother) to make sure the General gets the orders from the Emperor that he is free to act independently.
iirc, this is because the Emperor was assassinated and usurped by his greedy son, the Crown Prince, and so this paper gives permission to the General to maintain his authority. many other princes in the meantime have been trying to dispute the Crown Prince's claim to the throne, and the Crown Prince even imprisoned Ah-ting's grandmother bc of all this (she fasted in protest and passed away).
the young wife was barely hanging on and hoping to reunite with the General, whom she admired, but it seems the cultivators protecting her died and so did she. 😭