Ugh, this cliffhanger. Also, I doubt she's 38. She's probably 28 or something, and it likely came to her as a shock that she was closer to his father's age than to his.
@cor3zone It was probably just that she was wanting to remember her youth, (probably nearing that big 3-0) and decided to wear her old high school clothes. Then, he saved her, so she wanted to thank him, but couldn't just show up as herself, because he saw her in her highschool clothes. Then, after the second time they met, she likely thought "It's fun to hang out with this guy" and wanted to do it again, without realizing the consequences of her actions.