Phases of Life!!

I really wonder what this life is all about.There are times when I feel that I am the most happiest man on earth but then comes a phase when I squander it all. Well, I love to play sports but because of this injury I suffered during 2 years back, I have to stay away from sports and other exercises.Sometimes I feel that God is partial. When I look at life around me I feel that I am the only one suffering, when all my friends play I just sit and watch,contemplating every moment of the day when I suffered this injury.Why does it have be me?? It is true god has given me a lot and I am very grateful to him also.Probably some of the successful incidents in my life made me a little proud.For all I learn is that whenever there is something I feel proud off,bang!! something or the other happens. All I can do is patiently wait for things to get better.Why cant it be that life is always filled with happiness no sorrows at all.A world where no man suffers everyone is happy.Probably the reason god does this is because he wants man to remember him always. God I will remember you always, for you are my best friend, my sole companion in life.I have enormous trust in you God. All I ask you is a life without sufferings.But one thing I must admit is all these suffering taught me to be bold.Half the cure for these endless sufferings is the mental strength. But there is a limit, whenever I lose my mental strength I feel God is not fair to me. God please have pity on me and put an end to these sufferings.