And perhaps some lives are not, but it has nothing to do with our inevitable death. We might deem an action or an enterprise as "for nothing" due to many factors, but not "just because it ends". How many examples can we come up with? Holidays, meals, sex, games, conversations... We choose to do them to enjoy them while they last.
Sure, life is somewhat different because none of us chose to live, but that makes it easier: knowing it will end, we might make the most out of it while we are here. It has to be worth it for who it can be worth.
God gave you this life, and you should live it for him. When we die how we lived on Earth decides where we go when we die, and how you are thought of after you have died. I want to live my life to honor God, and I believe that living your precious life that he gave you is one of the greatest ways to live your life for him. With everything he has done for us we should live our lives for him, to praise him, to worship him, and to overall enjoy whats left of our life through him.
You aren't given 60 years of life, so you waste it dreading death. You are given 60 years of life, so you can enjoy them and make the world better, so others can enjoy it more than you. You make 60 years of life sound like a horrible limitation, but by the time most people turn 60 they've done most of what their life goals were while living a long and good life. Also we don't build friendships, because we have to, we do it because we like to have friends. We shouldn't work just to keep ourselves alive or our lives are wasted. Instead we should work to support our families, learn more, support charities, and support the things that will out-live us, while have a good fun life in the process.
It is true I am a nihilist, And I have reason. All humans gets killed sooner or later, Some might die young some old. Every knowledge, Every accomplishment you attain has no meaning to it. At the end, When you die you lose everything. You only go to eternal happiness or eternal torture. Life is a non existent illusion that don't mean anything.
It takes years to build friendships, we work around 60 years of our lives, we make money, we get attached to people, we do everything to be accepted around us, and at the end we're keeping none of those, so why are we really doing any of these things? Are we really here in a place considered 0.0001% of the universe to just do all those things and die at the end?