I don't know if this is exactly the right place for this to go, but Open Discussion didn't seem right for it.

I'm a habitual nail-biter, and it's starting to hurt when I play guitar, especially songs with lots of bends in them. I would stop, but I do it almost subconsciously, and I find my nails have been chewed away to nothing before I even notice I'm biting them.

Have any of you ever had this problem? How'd you get over it? Is there some sort of nail-biting patch I can wear?