What Is The True meaning Of A Hug?

Don't you hate it when you think something is going to go one way and it goes another way entirely? That's how I feel right now. I thought I knew that a hug was a symbol of affection shared between two people who have mutual feelings for each other. Clearly I was wrong. Apparently, a hug is a meaningless action that any two people can engage in. Even if one of those two people currently has a girlfriend. So, am I crazy? Mistaken? What are your experiences with hugs? Have you been in my position? Please comment.