Good luck figuring things out and feeling better.
Maybe once you can get your immune system to calm down a bit, you might be able to introduce milk again in moderation.(That has worked pretty well for my DD with milk, btw. But it's taken many years to get to the point where she can actually eat dairy products without tracking her intake fairly scrupulously.)
This is the case for me with a few things. When it's not pollen season, I can do small amounts of tomato, barley, and bananas. But I have to keep track and not eat too much...if I had a meal with all three, there would be hives for sure. Not a serious reaction, but enough to be uncomfortable.