Lygophobia! Scotophobia! Nyctophobia! Are you afraid of the dark?

But I've met adults who really, really, are. Have you ever had to handle something like this as a grown-up? Do you make fun of them or is it something you talk about real calmly like.

I've used it in the past as an excuse to be lazy. "Could you go lock up the front door? It's creepy and dark in the living room." You know, when we're both in bed and I don't want to have to find a bookmark or move.