Hi Ashley,Sorry to hear you're having that problem. I'm sure I've had that before, but not for a long time. While I'm sure you've probably already searched the internet for ideas, here are a few I found that discuss cause and treatment. Hope they're helpful!
www.livestrong.com/article/308669-what-causes-dry-corners-of-the-mouth/www.dailymail.co.uk/health/article-1100482/Ask-doctor-Why-sides-mouth-splitting.htmlhealth.msn.com/health-topics/skin-and-hair/preventing-cracks-at-the-corners-of-the-mouthHere's hoping they heal quickly.
Good luck!
Denise