There are mannnnny reasons why someone would get sick (some simply physical, yes!). I have heard many people, once over a debilitating sickness, say, 'Ah! NOW I know why I was sick - I learned this and this and this...I wouldn't be where I am now...etc etc'.
Maybe your path is to be a Healer? And usually healers need to go through the experience first hand in order to help others...