Steriods are not used long term
Many try to avoid them at all costs
Some use exclusive enteral nutrition ( formula only no food) to reduce inflammation instead especially in children
But sometimes even that doesn't work
Steriods are a "rescue" med that is used to get the inflammation under control so that your maintainance med ( 5-Asa in your case) can take over and keep the inflammation from coming back and doing more damage.
Symptoms are not reflective of the extent of disease
Tagging Clash
Here is the ccfa presentation on the risks vs benefits of the different drugs used in crohns
http://www.ccfa.org/assets/pdfs/risk-and-benefits-transcript.pdf
Hopefully 5-Asa will work for you . Typically though they are not enough alone .
The first year or so is very hard just from learning all of the different med and symptoms and finding the right combo that works for your crohns
There is no right answer and what works for one doesn't necessarily work for another
Good luck