There's a friend of mine—let's call her Lily—and a guy—David. Lily told me that she feels very happy each time she meets, talks, plays games, dines (and so on) with David. I guess she's falling in love. But she is very perplexed these days, because she likes him, but can't be sure — wants to but is afraid to make sure — whether David likes her or not. So she has decided to write something about that emotion, rather than telling David directly (thus prompting him to say "yes, I like you too").
Here is my question — for what perplexes her has also perplexed me:
In what Literary and Artistic way can she describe that emotion?