"Life is too short" is also the core tenet of a philosophy called "Memento Mori" (remember that you will die!). It was even used as a greeting, instead of "hello" by the members of certain religious sects.

https://en.wikipedia.org/wiki/Memento_mori

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But the opposite is also true: while I am alive, I am never dead (as silly as it sounds). I never experience death. For me it is an eternal now which is always alive. Should I worry about things I will never experience? We only experience the death of others, we don't know what it is like not to be alive 100 years from now. Why should we care about that when we are in an eternal now that is always alive?

One way to deal with death is to leave something of you behind - kids, ideas or social impact. Another way is to remember that there is a great number of people who died as well - everyone before a certain birth date in fact. It's not like going in a strange place, it's like going where all these great people went before us.

When we die we're divided - the matter that was in our bodies goes to earth and is recycled in nature, possibly becoming part of another life. The genes pass on to our kids and our grandchildren, then spreading out in a vast number of people 10 or 20 generations later; genes have a life of their own. The ideas we had fly from mouth to mouth, having a life of their own as well. The memories are left with our friends and family and will have a second death when they die. But does it matter to you if you're remembered by someone who is not close to you? The life that was in us just reinvents itself again. We're split into pieces and every piece goes right where it should.

Another thing to ponder about: what else is a lot like death? In a sense, it's the time before we were born. It was like death, because we didn't exist, and then we came into being. How was it before we were born? Was it a bad experience? We have had eons of death before our short ~80 year span and it didn't affect us negatively one bit. If we're not affected by the 'no-life' of the time before we were born, why should we be affected by the 'no-life' that will be after we die?

In the end, what is important? I think all reasons in life are related to survival instincts. Even learning to walk and grasp, or how to function as a member of society, or how to date and how to raise children - they are all in the service of self replication (and protecting one's life). Our fundamental reason for being is self replication, and all our "good things in life" come from things that support it. Thus it is this recursive loop that creates the root value (that of being alive) and from it come all our other values.

But this kind of thinking is relative. When we're lifting ourselves from the basic loop of survival, we see how many of the things we hold dear and important are irrelevant. There is no universal good or reason to be. Meaning is being invented every moment and we're in control of it. We should think ourselves free and ignore the survival game as much as we like. That's the beauty of it - we're free to reinvent ourselves, or to embrace our instincts and values, which have been chiseled by countless generations of genetic selection before us. One strategy is exploration (there's no rule, we could be anything), and the other exploitation (holding dear the good things in life, those which fit our survival instincts). They're both valid.
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