Jesseree was one of the few people who survived the tide. She and her two children were able to go to the church just before the tide reached the gates of Darkholme. In the end, they lived for another day.
Jesseree was aware that their lives would completely change after the tide. She had already prepared herself to move to another place. As a single mother of two, she would do everything for her children to live another day, and she knew that they would not be able to do it in the ruins of Darkholme.
So, when the knights asked them to leave, she and her children were among the few people willing to leave Darkholme and find another safe place.
The chaos with the Reverend was something she never expected. However, something even beyond her expectations happened. The last trace of the barrier that was protecting the church crumbled, leaving them defenseless. And to her horror, another beast tide indeed happened just days after the first one.