If ever you think your life is miserable and you start to get downhearted then I have a book I recommend you read "Man's Quest for Meaning" by Victor Frankl.
Frankl was born in Vienna in 1905 and even before the outbreak of World War 2 was an accomplished academic and psychotherapist. He was also a Jew and, along with his entire family, was imprisoned in a concentration camp. Man's Quest for Meaning documents his personal experiences of Auschwitz and other camps. Only he and his sister survived everyone else who mattered to him: his wife, parents, siblings and friends were killed. A good summary of his life and work is provided by Dr. C. George Boeree here.
After the war, Frankl reestablished his career and produced this remarkable book which soon gained a substantial readership and acclaim.
I remember my reluctance to read the book - I was afraid I would find it depressing, after all, life in a concentration camp what could be uplifting about that? The opposite was the case, I was genuinely uplifted and this is is precisely the point that comes through in the text. If, even in the most forlorn circumstances, in the depths of hopelessness and the most inhumane conditions, if even there and then, people seek to bring meaning into their lives, they strive to build things, to organize, establish relationships and cling to ideas - this is surely an uplifting insight on our very existence.
Recently I found this web clip of Frankl - watch and listen to what he says here and read the book. You'll find it difficult to moan about our own trivial challenges in the future.