Thanks for posting your query at DoctorSpring.com
I can understand your concern.
This seems to be contact dermatitis. It could be either due to lip licking , lipsticks or lip balms that you may be using or spices and nuts that you already mentioned. It doesn't seem like a fungal issue.
I am sure you have tried to avoid all irritants that you could think off. However in case you have a habit of lip licking you need to stop that.
The treatment would be application of a high potency steroid cream like mometasone furoate which would require a prescription.
Avoiding all irritants is the key to treatment.
Also adding an antibiotic cream like mupirocin will help treating any superadded bacterial infection that might be present.
Please let me know if you have any queries.