Bonnie was oblivious to what Caroline was feeling right then, having fallen out of tune with her friend's emotions long before she became a vampire. That was Bonnie's fault, even if she didn't realize how much it hurt Caroline.
For a moment, she considered taking Caroline up on her offer before she decided that it would be better for everyone if she was alone when she went through Emily's grimoire. "No, that's fine. I'll check into a motel." She had enough cash for a day or two and that's all she really needed until they left for Mystic Falls.
If Mystic Falls was there.
"We'll need weapons though. What if we explain what we're doing?" Bonnie asked, lifting her straw to her lips and getting nothing but melted ice. She looked mournfully at her empty coffee cup and sighed.