Marisol grew extremely worried about Cedric's well-being, and it was during that time that she noticed the increasing jumpiness of her own wolf, along with a noticeable shift in the atmosphere within the pack.
It belatedly occurred to her that a full moon was around the corner. Rumors began to spread within the pack. Pack members had witnessed firsthand the devastation Cedric could unleash when his wolf took control, and they were rightfully wary of what was to come.
While the full moon reduced every single werewolf to their savage form, Marisol realized that it would be much worse for Cedric. If it amplified the darkness that already lurked within him, that would be the same as driving him to the brink of madness.
As much as the realization filled Marisol with a sense of dread, a part of her relaxed at the explanation it provided for his sudden possessiveness.