Life is worth living, when you live it without thinking of what people will say about you.
People see life in different ways.. some say life is frustrating because of the things that they have been through in life, for example a guy that graduated in the university with first class regardless of how he suffered to pay his fees and now roaming about for five years now without a job will say "life is frustrating"
Another from the other hand will say life is sweet depending on what his or her own experiences was. So everyone gives a definition of whatsoever they feel is life.
I will say, life is like a pool covered with water, river or ocean, when you jump inside it(born), it is either you swim out or you you allow it drown you.
Again life is like a circle moving in it's axis without much velocity which accelerates it's motion, but can be propelled by our drives.
The reader here is the only one who can tell what life is, give a full definition of what life is to him or her...... The definition can't tell you the meaning of you tell yourself what life is. Don't look at life in the negative aspect always proclaim the positive.