Advice please!

I currently have a wound on my cheek. It is slowly healing, but is going to leave a scar. Recently I have been going out without a bandaid on. What I am having trouble with is when people feel like it's okay to say something about it! I had a woman today ask "What happened to your face?" And it wasn't the first time this has happened. It ruined my day. Does this happen to anyone else? How do you handle it?