Corn Snake will not feed and is not molting

[melbry]

Hi all, first time snake owners here. We've had Petunia, our Corn Snake, since last October. She's been a champ at eating every 7 to 10 days (a small to medium sized rat purchased at a local pet store, kept frozen and brought to room temperature right before feeding). Sometimes she will strike at the rat and grab it immediately, and other times she prefers to have it laid in her cage for later consumption.
She has only shirked food when she was about to molt. Her last shed wasn't too long ago (a month or so), therefore, it doesn't seem that her lack of eating now is due to that. Cage temp is normal (nothing varied there). Access to water at all times...she looks normal. What could be another reason for her lack of eating? She won't strike at it, though she flicks her tongue and checks it out. And she won't consume it if it's left for later..It's been about 2 weeks since her last feed, maybe a couple days more. Help!