Excellent points and very well said. Recently I have been starting to feel down about myself and I noticed that it had to do with reading Hacker News and estimating my value through the lens of this startup value system. Despite the obvious talent and intelligence in this community, as you pointed out, if you are constantly face to face with a value system that is at odds with yours you will either (a) decide that it is not for you and walk away or (b) if you are of a more impressionable mindset, you may start to wonder why you don't match up. In my case, I have been finding the latter, at the expense of my self-esteem. So perhaps, as you suggested, I should take a break from HN for a while, as seductive as it is both in terms of content as well as the quality of the discussions.
I found myself going through faces of obsessive determination and complete apathy last year. I think part of that's probably just life: Everybody runs into dilemmas. In cases like this, where partly it's a matter of being online talking to a focuses set of people, taking a few months off works wonders. Turn on noprocrast, set your away time to 65536, and figure out what else you can do. I just got access again a few weeks ago, and I don't feel the pull of this community anymore, so I don't feel as committed and frequently hopeless. With luck something like that could help you out as well.
(My other, snarkier advice is to go to Metafilter and look at every thread regarding a Paul Graham essay, because Metafilter's a bright community that loathes Paul Graham. My opinions are somewhere in between there or here, but reading those threads in June was rejuvenating in some ways.)
Thanks for articulating that so well.