You already answered the question yourself, Bro. Life is really Unfair to some extent.
If you were born into a very rich and wealthy family and you are having it very easy and enjoyable for you it won't be unfair.
But if you were born into a poor and broke family and life is very tough for you, It is unfair.

So we just gatta live with that fact in our minds. The most important thing is trying to be happy in life.