Seriously I just think this exfoliative cheilitis is the result of repeated trauma then, for me at least, the compulsive rubbing of my lips together, which lead, on the one hand, to a kind of scar tissue (the triangular part is the best evidence) and on the other hand a kind of crumbly tissue regarding the bottom lip, like if the damaged area was in a lower quality than the rest.
I agree our condition looks like actinic cheilitis except that it is just affected superficially, maybe we have too much damaged our vermilion to prevent it from coming back to normal.
Shit, I still have my colonoscopy planned but it's about 450$ under general anaesthetic and I'm pretty sure that nothing will show up. I'm very hesitating.