I just looked up Crohn's disease: an inflammatory bowel disease and eczema is an inflammatory disease. I see why your case is complicated. Eczema is an auto-immune disease and many of us with eczema have another auto-immune disease, for example I had leukemia. I thought Crohn's was an auto-immune disease but recent studies are discounting that.
I did forget to mention taking Chlorella like mariannj mentioned. Yet I also take a bunch of other herbals recommended to lower inflammation, like oregano. I either take the oregano oil capsule or add fresh oregano (it grows easily year round in my zone 6) to my cilantro smoothie, yet I had been adding oregano since last October and had a GD re-occurrence start in Feb/March. The oregano I am sure is helping with lowering my yeast and overall inflammation. I know Crohn's is an inflammatory bowel disease and the reason I add oregano is that it helps control the residual hard to kill yeast that lives in the bowels. The yeast is a living entity and the waste it gives off raises our histamine levels. Ever wonder why we get sugar cravings? Your yeast is demanding to be fed.
Going off sugar now for almost a year I never look at a dessert and have my mouth water because the yeast isn't screaming to be fed. We are all here to learn and share ideas and yes try anything that doesn't seem dangerous.
Your doctor brutally shared with you, "GD is really gonna just suck for you". My new young derm took one look at me and almost got giddy! Saying, "Wow, you have GD and I only get to see about 1 case a year". I had never heard of it before. I went to my favorite eczema site, dermnetnz.org and looked at photos and descriptions and don't see how other derms could have misdiagnosed it. Still I am grateful she figured it out in one look. At least being told I had GD gave a name to my tormentor, even after I learned nothing much helped but time. My first outbreak was 1 full year and then for 4 years, 6 months on and 6 months dormant. Also be hopeful as my subsequent outbreaks were not as completely debilitating. My symptoms were about 30% less severe. Awful yes, but better. As I often mention, going to many different dermatologists has made the difference for me as I often learn something new.
I hope you will have success like many of us have had. I wish more GD sufferers knew about this treatment. I wrote up my history using cilantro and included info on accessing our GD blog on the Mayo, plus the earthclinic site Kimass1 turned us on to and gave it to my local derm and will bring this info it to my Western derm when I visit this fall. I want them to mention this to their patients, as I think it helps about 50% of us. My local derm had never heard of cilantro helping.