Where am I heading?

Many time I think about this...some times in the office, some time when chatting with friends..and some time in he midnight when sleep goes away...what is meaning of life of human being? OR what is the aim of life ? of course second one is quite personal and unique for each individual. I am a software engineer. I earns good money. For complete day i work like firefighting force in the office. With time I will get marry, and will get children and so on...cycle will start repeating...Many times I remember my fathers sentence" if eating, drinking and enjoyment is the only aim of life then what is the difference between life of human being and animal?" What one is adding in this world OR simply in other life by living? I got so confused..what is the aim? only work for eat and eat to work is simply unacceptable.