so I spoke to my doctor, concerned it was some sort of STD or fungal infection on my face...and she sort of put that to rest because I would have sores or blisters around my mouth if it was herpes. Then she brought up the fact that her husband sometimes doesn't shave and it makes her skin dry...and even a 5:00 shadow, if you're making out with a boy, can really irritate your skin. This was the problem for me, though the problem was definitely exacerbated by Boston's dry winter air.
This seems SO simple and I didn't even think about it, but it seems like a very viable solution
Good luck with your problem, I hope that can help you too!