There are usually two different reasons for blockages in patients with Crohn's. The first is due to severe inflammation or swelling of the intestine. It literally swells shut. This is sometimes referred to as a stricture.
The second reason is due to scar tissue that may form after the swelling has gone down, just like the scar tissue you may get after a cut heals on your skin. Because the injury to the intestinal wall may go all the way around the circumference of the bowel the scarring can result in severe narrowing of that section of intestine. With repeated episodes of swelling and scarring you can end up with such a bad stricture that no food can pass and it must be surgically removed. These sections of bowel are also referred to as strictures. Very severe stricturing may be referred to as showing "string sign" because the bowel looks like a piece of string it has become so narrow.
When you are in an active flare of Crohn's it can be difficult to know if the narrowing is inflammatory or not. Usually your doctor won't know until you are in solid remission.
My son had extensive stricturing at the time he started Humira 4 years ago. At that time his doctor thought that much of that structuring might be scar tissue that was not going to resolve. But a recent MRE showed no strictures at all.
To be frank, nearly everyone who has Crohn's requires maintenance medication to modulate their immune system. It is out of whack and needs something to keep it in check. I think of it as an engine that is revving too high. The meds help stop the revving and bring it back into the normal range. The revving is hurting your body and is very likely to damage it so badly that you will require further hospitalization and possibly surgery unless something is done.
Some people use dietary and other approaches to manage their CD. In general I believe these methods don't work over the long term but you should check that out and decide for yourself. Some people find success combining diet and meds so that they are able to use lower doses or a less intense level of meds to keep their CD under good control.
The bottom line is that you should talk things over with your GI and consider taking his/her advice on these issues. GI's go through a lot of training and have a lot more experience taking care of people with Crohn's so they usually know what works and what doesn't.
Best wishes