If you file I-485 (I-130 should be filed before or at the same time) for her, she should stay till receiving her green card. Otherwise, usually, I-485 will be considered abandoned and she has to re-start I-485 in the future. Also she may have trouble to re-enter US after abandoning her I-485 (leaving US before receiving her green card or reenty permit.)
However, you can file I-130, I-485, I-765 and I-131 concurrently for her. Once she receives the EAD (工卡）， reentry permit will be included. Then she can travel outside US and re-enter with her EAD and I-131 before receiving her green card.
