Literally the only book I've ever recommended to anyone is Dr Viktor Frankl's
Man's Search for Meaning
http://the420formula.com/new/headshop/books/pdfs/Mans-Search-for-Meaning-Viktor-Frankl.pdf
It's a pretty quick read (less than 200 pages iirc) but the impact it had on me in my life was profound
A few exerpts from the chapter "The Case for a Tragic Optimism":
Most important, however, is the third avenue to meaning in life: even the helpless victim of a hopeless situation, facing a fate he cannot change, may rise above himself, may grow beyond himself, and by so doing change himself. He may turn a personal tragedy into a triumph. Again it was Edith Weisskopf-Joelson who, as mentioned, once expressed the hope that logotherapy “may help counteract certain unhealthy trends in the present-day culture of the United States, where the incurable sufferer is given very little opportunity to be proud of his suffering and to consider it ennobling rather than degrading” so that “he is not only unhappy, but also ashamed of being unhappy.”
...
The third aspect of the tragic triad concerns death. But it concerns life as well, for at any time each of the moments of which life consists is dying, and that moment will never recur. And yet is not this transitoriness a reminder that challenges us to make the best possible use of each moment of our lives? It certainly is, and hence my imperative: Live as if you were living for the second time and had acted as wrongly the first time as you are about to act now.
In fact, the opportunities to act properly, the potentialities to fulfill a meaning, are affected by the irreversibly of our lives. But also the potentialities alone are so affected. For as soon as we have used an opportunity and have actualized a potential meaning, we have done so once and for all. We have rescued it into the past wherein it has been safely delivered and deposited. In the past, nothing is irretrievably lost, but rather, on the contrary, everything is irrevocably stored and treasured. To be sure, people tend to see only the stubble fields of transitoriness but overlook and forget the full granaries of the past into which they have brought the harvest of their lives: the deeds done, the loves loved, and last but not least, the sufferings they have gone through with courage and dignity.
Every single day of your life matters
*Dr Frankl was a neurologist and psychiatrist and survivor of Auschwitz and Dachau concentration camps during WWII. His entire family -- his wife and parents -- would die in the camps
