He lets it go because she clearly doesn't want to address whatever it is that's on her mind. Hopefully, she'll open up to him later. She changes the subject and he nods a little, ducking his head toward her.

Another time. Maybe it will be better to have this conversation some other time, some other place. It's one they should have though because her insecurity is unfounded. Of course, he doesn't realize that his insecurities and concerns about falling in love with Lydia are unfounded as well.

He leans his head into her touch, softly sighing in contentment at the feel of her fingers against her scalp. "Mmmm very nice," he agrees.