It sounds more like the cause could be Increased Digestive Permeability aka (wrongly) "Leaky Gut".
Your seemingly food sensitivities and sensitivity to sunlight? can be due to raised cortisol and liver heat which could be a result of IDP. Your home move and the stress involved could of weakened your adrenal glands which would of made the problem more pronounced. Licorice supports the adrenal function. You say that fasting helps which it does with illnesses such as Chronic-Fatigue-Syndrome because it provides relief to the liver and immune system.