It may be her. But, she seems to have a warped sense of purpose. Once The Other Tower was hit by zombies, she seems to be more preoccupied with keeping tabs on Durai than assisting what is left of humanity survive. Maybe she is working for a higher source that has ensured humanitys survival and Durai is the biggest threat. Maybe she has had a Crissis of confidence even greater than Michael's.

But her most recent action is a break from what we know. She has spent two months observing and avoiding contact. Now instead of avoiding Saul and slipping away, she opted for a poorly staged and executed attack. Of course she may be such a master mind and planner that she intended to get captured.