I Don't Get that other-people can apparently be very happy, without (almost simultaneously) recognizing the tragedy of this mortal life

For me, it always has been that when I am most happy; I am also saddest - most aware of the tragedy of this mortal life. 

For the (to me) obvious inevitability of change, and eventual death - so that the happier, more perfect, more fulfilling, deeper and more wonderful is a moment, a situation - the sadder awareness of its inevitable demise. 

Indeed it is gone even as we think of it.

And there is no answer to this, in this world - except for the destructive non-answer of "don't think about it". 

(Which is the modern answer; compounded of massive-and-continuous distraction plus intermittent intoxication and/or mental blunting.)

This non-answer has the consequence of destroying happiness and appreciation, in order to eliminate the sadness at its inevitable demise. 

But; unless we can each of us grasp that this mortal life is most tragic when it is best; then perhaps we cannot grasp the magnitude of Christ's gift of resurrected eternal life?

Note: I was very aware of the tragedy in happiness of this mortal life long before I was a Christian; indeed from my middle teens. The difference was that I could never discover any solution to the dilemma, and I misunderstood (and disbelieved) the Christian answer - which I falsely assumed to be the assertion that the tragedy of this life was somehow compensated by happiness in the life to come. Therefore, the only viable possibility seemed to be to try and ignore or blot-out awareness of the phenomenon (as nearly everybody does, apparently, nowadays, in The West at any rate). Currently, I realize that extremely few Christians apprehend the problem, nor do they understand Jesus's solution to the tragedy of this mortal life. As usual; it's all too simple, clear and obvious - too childlike; to be graspable by the abstraction-addicted and this-world-bounded Western mind.