Hi KMarie,
Welcome to the board. Your symptoms, medical history, active lifestyle, and response to Entocort are typical of many of the members here. You are fortunate to have a doctor who understands budesonide well enough to allow you to use Entocort that long — most doctors who prescribe it are afraid to allow the patient to use it long enough to accomplish anything worthwhile. You still have time to modify your diet in time to allow sufficient healing so that hopefully you will be able to maintain remission after the Entocort is discontinued.
In a nutshell, even though we always test negative to the classic celiac blood tests (unless we actually also have fully-developed celiac disease) all but a very small percentage of us are just as sensitive to gluten as the average celiac, and many of us are more sensitive to it than the average celiac. Most of us (probably at least 85% of us) are also sensitive to casein (the primary protein in all dairy products). At least half of us are sensitive to soy and most or all legumes, and some of us have additional sensitivities as well. For most of us, though, those are the main offenders, and if we eliminate them from our diet (100%) we can maintain remission without any medications.
IOW, once MC is triggered, the genes that predispose to certain food sensitivities are also triggered. From that point on, if we continue to eat those foods, our immune system launches an autoimmune-type reaction against them (and the interior of our intestines, since it's in the line of fire also), and additional inflammation is generated every time we ingest one of those foods. It takes much longer for for the intestinal damage to heal than most doctors realize. Corticosteroids (such as Entocort) can suppress the inflammation, but some of us (including yourself) generate inflammation faster than the drug can suppress the inflammation, so the clinical symptoms of the disease are not completely resolved.
Changing your diet to avoid those foods will allow the inflammation to come to an end, so that your gut can begin to heal. It's as simple as that.

Of course, most people don't consider diet changes to be easy, but trust me, it's far, far, better than running to the toilet and/or taking powerful drugs for the rest of your life. If you are concerned that it may diminish your athletic performance, please note all the celebrity athletes who have adopted the GF diet in the past few years. According to them, their diet changes are the key to their world-class performance, rather than a handicap.
If you would like to verify whether or not you have any food sensitivities, the only reliable tests are the stool tests offered by EnteroLab (right there in Dallas). Dr. Kenneth Fine, who is a GI specialist, owns that lab and created the testing procedures. He has MC himself, which prompted him to find a way to actually resolve the symptoms, rather than to just treat the symptoms, the way that the medical profession tries to do. Unless we avoid the foods that trigger the inflammation, once we stop taking the drugs, we are right back at square one. You can check out the lab
here.
One of the worst features of this disease is extreme fatigue (the Entocort tends to mask fatigue, as long as you are taking it). Believe me, you will have much more energy after you get rid of the foods that cause the inflammation. Foods that inflame our intestines are not our friends, no matter how difficult it is to face that fact. Contrary to the propaganda that we have been fed all our lives, wheat is not the "staff of life". For those of us who are sensitive to it, it is a toxin that our body will no longer tolerate.
We have a number of members who have gone through pregnancy with this disease. Most are not currently posting, but their stories are in the archives. Basically, if they have active MC, the hormonal changes that occur during pregnancy can make the symptoms worse, or they can make the symptoms resolve. The odds are about 50-50.
Again, welcome aboard, and please feel free to ask anything.
Tex