I think that everyone has a unique experience with remicade. I used it for three years after a remission I was in started to break down. In my first year, the remicade reduced the flares to 1-2 per year and they were fairly easy to deal with. As I was in grad school at the time, I would use prednisone for a few days to get over them when they happened (40 mgs/day for 2-3 days). Could eat and drink normally after that. By year 2, they were becoming more frequent, say 4 per year. By year three, we had to start increasing the frequency with which I was getting it from every 12 week to every 8 weeks. We even tried adding a few other meds. In my case, I was stricturing, building up scar tissue that was narrowing the space inside the bowel. Remicade reduces inflammation, but does not repair stricturing. So, you can flare while on remicade especially if the disease is diet sensitive and you are building up scar tissue. Ultimately, I had surgery to remove my ileum.
1) So yes, you can flare on remicade. When my disease was inflammation based and not scar tissue based, remicade worked to reduce flares and make the 1-2 per year I had easy. I would ask your GI to give you an idea of how much scar tissue is there and how much inflammation is there. That will give you an idea as to where you are headed.
2) When you move the doses closer togther it does mean the effectivenes is reducing. Again, it may be scar tissue and not inflammation. The other problem is that people develop auto-antibodies against the remicade. They effectively neutralize the remicade making it ineffective. So, more remicade is required to acheive a therapeutic level. This is very common and varies per person.
3) I always used steroids to help with flares. It made life easier. Allowed me to go to school, work, etc. Usually I would notice improvement in 4-6 hours after taking them.
Long answer, but I hope it helps. Hang in there, I know how ya feel.