Speaking as someone who loved Audrey Hepburn, I think your friend gave you a beautiful compliment. Audrey was so graceful and elegant, as well as beautiful. I often find myself comparing people to others, not in a negative sense, but because they have similar features. Just last weekend when I was at dinner I noticed that my waiter was a male version of Angelina Jolie. My friend had to agree because they have so many facial features in common. While Angelina may take offense at the thought, it was not meant to be at all offensive. He just looked like he could her brother.