Agree with what B. says about 'expressions of affection'. If you really LOOK at that well-worn phrase ... it's all about, well, what it says. A physical gesture to demonstrate YOUR affection towards HER. Believe me, I've so been there with the "But I'm hugging you .... why won't you hug me back?" In the end -- while it's normal and natural and human to want to have your affection returned -- that there is a covert contract.
I got a lot farther -- mostly inside my own head, but also in real relationship terms based on what energy I was silently vibing -- when I started showing affection because *I* wanted to -- no strings attached. It's not a bad exercise.
"Show me a completely smooth operation and I'll show you someone who's covering mistakes. Real boats rock." -- Frank Herbert