Any happy living being will not find satisfaction in death. You just have to take the existential outlook that you may die or be immortal, in either case you have to define and strive for happiness. I remember as a child thinking "death will never happen to me." I also used to find refuge in belief, until I realized it was just a delusion.

I found that liberating, though. If life is here for a moment or forever, it is best not to let death define it. Just live.

Richard Carrier has a few essays on secular valuation of life; you might want to check those out. Keep striving...