Hello, I always get cold/lip sores from kissing. I'm​ in a long distance relationship so the last time I kissed my boyfriend was 6 months ago, and we kissed a lot and I thought I got the lip/cold sores from excessive biting. But again this happened recently, we kissed a lot but this time we both were pretty careful about things, but again i got lip/cold sores after 2 days. The point is he doesn't have any mouth infections or cold sores or anything, but it just happens to me I don't know why, please help me with this, how to avoid this, or tell me some medicine so that I can heal them fast. Thank you.