What is reality

Yesterday my older my brother  sat down and started talking  about his love life and how he regrets everything he did. But then more later he started talking to me about how each person always has to make a sacrifice whether it means you lose the people you most care about or become happy in life. He also told me that once teenagers start growing up they start to notice the mistakes they make and realize that the only thing they did was waste some of their time just partying and messing around insatead of thinking what might happen to you more later on. What my brother said got me thinking to myself about if we waste so much time in parties why de we barley realize when we start to mature? Also about how at first you thought life was only a game and didn't really matter but in reality life matters a lot beacause then you will be missing out in so many things in life then in just going to parties because once you realize how reality really is then you will be able to follow the path you know is right for you.