There is absolutely no reason for me to write a single word on this topic when you can get most of it elsewhere.
Please read Causes of Sickness
The author adds a new thought to me. He (she) said that in Holy Communion the bread signifies salvation of the soul from sin, and the wine was for the removing of sickness. Some denominations have no wine at their services. Those of you who have such limitations should examine whether this is one of the reasons you are suffering.
In either case, God does nothing without the cooperation and agreement of the believer. Nothing is automatic in His world.