To follow-up on my previous post, I watched a relevant Ted talk the other day: http://www.ted.com/talks/elizabeth_gilbert_on_genius
A popular writer describes why being an artist, or more generally, being creative is so hard on a person - you get subjectively evaluated for your creations, you have to worry about not having enough creative ideas to fuel you further, you continuously have to compete with yourself (specifically your own creativity and imagination). And all of this can lead to depression (a depressed creative genius is not a rare sight).
She mentions that the ancient Greeks and Romans got it right: they attributed creativity to an external spirit that either did a good job or not. This is the type of thinking that could shield an artist from his creative genius, making creativity an external factor. A successful artist need not suffer from narcissism, an unsuccessful one need not blame himself (rather, blame the lame spirit).
I came to the same conclusions about the difficulty of being a grad student, and for the same reasons. Grad students are creative individuals, that first have to conjure up new problems... and then, solve them. Learning to separate oneself from one's ideas can do wonders for sanity.
Here's a possible approach: when you come up with an idea, step aside from it (go as far as sending yourself an e-mail with the idea or leave an "anonymous" note on your own desk). Pick up the note, read the idea, critique it (praise the idea, or politely refuse to follow through with it). If the idea doesn't end up succeeding in the long run, shrug your shoulders: the anonymous note writer might leave you a better idea next time...
post scriptum: I often catch myself unable to fall asleep because all the good ideas start coming at 1 am. There's many of them, and they're all scattered. Paralleling Liz Gilbert's story about the poet on the road, I want to shake my fists at all this "external" creativity and yell: "just let me sleep once in a while, will ya? come back tomorrow morning when my brain can sort through all this")