The whole point of Monty Python's "Dark Night" sketch was because Cleese wanted to show the ridiculousness of the statement of "always persevere".

http://en.wikipedia.org/wiki/Black_Knight_(Monty_Python)

I agree with your statements and am glad to hear you're doing well, but I think that sometimes, it is wiser to know when to stop and take a long, hard look at what you are actually best at. But at least most Silicon Valley startups don't make quadriplegics out of survivors.