Hello, Mouth sores that reoccur are often viral. Stress can bring on an episode and repeat. Have your mouth sores been tested? Simple swab, biopsy, etc.? See a specialist such as an oral surgeon. Visit a dental school or a dentist with a greater interest in oral pathology. You seem to still need more diagnosis. Systemic conditions are known to be associated with mouth sores such as HIV/Aids. Testing is critical to determine normal ranges and overall health. Your genetic history and family illness history may offer clues. Are you compromised? There are auto immune disorders. Students stressed can have Mono. Travel lately? Unusual exposure or diet change? Keep asking many questions. A history of Measles can later appear as Shingles. Mouth sores can be included in Shingles. Virus exposure history helps diagnosis. Having an association with another carrier of a virus such as Herpes can cause repeat reactions. Changing routines, limiting exposure and getting rid of items that might carry a virus are all good actions. You seem to have tried many actions. One other consideration is an allergic reaction to your dental care products and make sure you have ruled this out. Try changing toothpaste or rinses. Flavorings and other ingredients are known to cause reactions. Symptomatic treatment with pain medication, rinsing warm salt water, avoid irritants and time passing is the best advice for now. I try to provide questions to help you think and you have the option to visit other doctors for continuing clinical evaluation.