Sorry to hear about your long term troubles.
I won't then suggest that you go see a dermatologist, as obviously you've had your fill of them and their myriad of medications.
I will instead provide you with a quote from a study I read. You can get a link to it here and read the entire thing yourself.
"In general, doctors tend to dismiss the possibility of a causal link between the diet and the incidence of acne. However, a large body of scientific evidence now supports such a link" ........"a study of 47 acne patients confirmed a causal link between diet and acne"......."Subjects who followed this diet showed immediate improvement in symptoms and eventually became completely clear of acne."
Good luck with it. I wish you well.