Anne Lamott is an idol of mine.  This from her book on writing, Bird by Bird, says it all:

Close your eyes and get quiet for a minute, until the chatter starts up.   Then isolate one of the voices and imagine the person speaking is a mouse.  Pick it up by the tail and drop it into a mason jar.  Then isolate another voice, pick it up by the tail, drop it in the jar.  And so on……..Then put the lid on, and watch all these mouse people clawing at the glass……Then imagine there is a volume-control button on the bottle.  Turn it all the way up for a minute, listen to the stream of angry, neglected, guilt-mongering voices.  Then turn it all the way down and watch the frantic mice lunge at the glass, trying to get to you.

There are a lot of reasons not to write.  There is really only one good reason to write, and that is because for some of us it is life.  It is voice.  It’s a long road, finding and honoring that voice.  Maybe writing isn’t your thing, but you have a mode of expression that is vital to who you are.  Just remember, they’re just mice. 

Tighten that jar.