The function of suffering

At times, I ponder whether or not suffering actually has a purpose. I have seen on many occasions famous individuals stating that they could not believe in God due to all the negative aspects of life which they have seen, such as a child in Africa that had worms eating away at his eyes. Personally, I seem to have reached the conclusion that actually, suffering could in fact be proof of God's existence, not to say that a God exists.
Why and how have I reached this conclusion? It's rather simple actually, and may be said to be too simple in fact. Nevertheless, the process with which I reached this conclusion is as follows:
It seems that in all life there is one thing which is constant, and that thing is opposites. With regard to most animals and plants for instance, there is a male and there is a female. These lines are blurred by such things as homosexuality, which shows a state whereby an individual contradicts the norm of nature, whereby a male mates with a female in order to produce offspring. The presence of opposites is in my opinion the manner in which the world is balanced. This has been called different things in the past, be it YingYang or Karma or whether it is implied through God and Satan, or indeed mentioned in such texts as the Quran.
If I hold that mankind and all of its religion and ideology are formed in order to enable a balance in society and therefore happiness , then I also believe that if there is a God then he enables suffering just as he enables joy or happiness or well being. Therefore the purpose of suffering must be to achieve joy, for if one had never suffered how could one enjoy certain aspects of life sincerely? If suffering did not exist, then we would take all of the things which make life enjoyable for granted. For instance, I enjoy cigarettes because I know that once upon a time I could not afford them.
Essentially, one of the ways in which I rationalise existence is that all the experiences that we have, or indeed all of the things which happen as a result of existence are there in order to give some form of structure and therefore meaning to life itself.
I dunno, hopefully someone will respond to this and give me another opinion.