Same for arachnophobia. Actually dated a girl for a couple of years that was eat up with it. Took me AGES to figure out why she was constantly scanning the walls while we talked on the coach. One night she laser-focused, pointed at a speck, "KILL IT!" I couldn't even tell it was a spider it was so tiny.
Also, when she opened cabinets, she'd chill and look in them carefully before sticking her hand in. Even then, she looked behind the can she pulled out.