Rough feeling on inner lower lip, inside cheeks and under tongue

I have seen some older related posts on this topic but see no meaningful answers. Part of the problem is that people aren't motivated to respond to something that was posted 7 years ago. So, here is a fresh take on the problem: For over 20 years, I have experienced a rough feeling on my inner lower lip and rough/bumpy inner cheeks and under the tongue. These are not "bumps" and don't have liquid in them. These are also not salivary glands - I know what/where these are. It feels like sandpaper (and no, I don't have drymouth) or literally rough surface, and this surface is somewhat weak (like old skin) and is easy to bite into (I am under 40, and this is not because I am falling apart - I have no HIV/AIDS or any autoimmune disorders). It started slowly when I was 17 or 18 and has gotten slowly worse over 20 years. For some strange reason, no doctor can identify/diagnose this, but most doctors (erroneously) confuse confuse this with thrush, or candida/yeast/fungal overgrowth. Hypotheses coming from various people and medical professionals all-over the internet include dietary problems (no, I have fasted - as in NO FOOD AT ALL, just water - for 14 days, and it didn't go away), allergies (no, this never goes away when you take even the strongest allergy meds), toothpaste (no way, I brushed my teeth without any paste for 30+ days and it stayed). There are TWO things that improve or eliminate this for me. One is alcohol (funny right?): if I drink a lot of hard liquor (vodka or tequila party time with old friends), chances are the next morning this will be gone almost entirely... but will always return within 24 hours (note: rinsing the mouth with alcohol has ZERO effect - I must drink it and must drink enough to be tipsy, if not drunk!). The other is antibiotics: every time I have taken antibiotics (e.g., azithromycin) for an upper respiratory infection (cold), the problems in my mouth go away for a few days... but then always returns within a week. Isn't there at least one good doctor who can diagnose and treat this? The rough feeling on the mucous surfaces inside the mouth is the least of my concerns. The problem is that I tend to bite and chew my cheeks and lower lip, which is embarrassing and uncomfortable... but most importantly, it exposes the resulting micro injuries to whatever foods and liquids I put in my mouth, which over many years can trigger tissue malformation and cell mutations... which can eventually turn into cancers. Doctors? Scientists? Does anyone have brains to solve this problem? Search the net for this: there are thousands of people with this problem, and no one knows what it is.