What is life? Isn't it just an opinion of the person who is living or the person who is related to it, in one way or another?
If I think my life is good and meaningful then of course I will see everything in a different and happier way. Its opposite is true too. If I think my life is not as meaningful at all and I am unhappy from the way things turned out for me. I will be sulking and remain such, unless something more dreadful or something very good happens to me.
Now let’s see this from others point of view. Suppose, for a moment it doesn’t matter what I feel inside, if I am happy or sad. The way I show and reflect to other people I will be perceived and treated respective way. If I am happy I will attract more people. If I stay sad for long, may be in the beginning people will try to make me feel good or cheer me up but after sometime they will stop being nice to me and might leave me as well.
I was something else but I showed them something different. For them my truth is what they perceive from my personality. So again this is merely an opinion of others about me.
These opinions, mine or theirs forms a circle. The meaning of life becomes how and what I think about it. If in my opinion booking a seat to heaven is the meaning of life then I will do every good deed to earn enough credits and then I will kill myself shunning any possibility of doing anything that might make me lose credits. So is doing suicide rational? No!
This whole idea of finding a meaning of life is a big lie I think. We become like a dog chasing his own tail.
I wonder if you didn't even lived your life till the end how could you even think that your life had reached a point where you should start looking for its meaning? Who knows that the meaning of your life won't change once you find it out?
There are numerous questions laying and creeping on the floor of human mind and no one can answer them correctly but he himself.
So I think first purpose of life is to live it. If you didn't, you will never be able to understand what was it is all about and what is its meaning.