I assume you're talking about celiac disease?
If you have already sought professional help I don't think there's anything new I can tell you besides the usual suspects like "grit your teeth and stick to the diet" or "find someone who can keep you on track like wife, siblings or friends".
That said, if I was in your position and if I couldn't tackle the problem in any of the standard ways, I'd take an NSAID like aspirin¹ on "cheat" days to temporarily suppress the immune system as an experiment and see how that works. I found a 1982 issue² of The Lancet where someone had the same idea and reports success with this strategy but I'm not even close to a medical professional and this is just one data point so YMMV, caveat emptor etc, etc.
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¹But not ibuprofen or other NSAIDs, those seem to worsen the problem — https://www.thedailybeast.com/research-shows-link-between-ns.... Aspirin however has its own set of side-effects (bleeding risk, may interact with medication you are already taking etc) so strict diet is still the safest, long-term solution for now.
²http://sci-hub.tw/10.1016/s0140-6736(82)90024-1: 650mg Aspirin, 5-15 mins before meals, not after. Again, this is NOT medical advice, it is just one data point.