*blush & giggle* was that an oblique compliment?
Awesome godzilla-picture by the way... I have a strong feeling I'm going to have to use that talking to people in the future, if you don't mind. It's beautiful.
and hmm... well if the italicized part does make sense (to me), then I'm not so sure it makes sense (that is, being helpful) to investigate. Here's why. Also for the record, I'm not sure of this at all, and I wouldn't have probably mentioned it at all if I had anything better to say except "yes, you are making sense to me." I figure you can decide if it's good advice or not... so for the sake of keeping the conversation going...
Suppose that it is something unique that you're dealing with (which, if you couldn't tell, I don't think it is). There are only two effects that I can think of in investigating. The first is that you're likely to become even more upset and depressed over the fact that you're alone. Regardless of intp stereotypes, we all need at least some close relationships and reading between the lines of peoples' posts I'm pretty sure that most everyone hungers for them. I know I do, and judging by your post you do too. If that is actually one of the things you hunger for in life, finding out that no one else is dealing with the same thing is going to be devastating (considering it's causing you so much worry). Secondly, you'll just have wasted a lot of time and effort because no one else would understand the problem any better than you do, so no one will be able to offer much advice. They won't be much help and you'll just be left feeling more alone and depressed because of it.
Then suppose that it's a universal problem, or at least a fairly common one. For this... I mean... let's be honest... intp's are widely known (if internet portraits are at all accurate) for having the highest precision in their thoughts. We make distinctions, see connections, and find logical flaws in theories better than anyone else. Of course we're insecure about that ability, and tend to deny it and (I, at least) feel extremely uncomfortable when someone compliments me on it... but because insecurity is
also widely acknowledged in the portraits I think to be reasonable we should probably take both seriously. If this is true, then, you, being naturally equipped for the job and having put so much energy into merely
discovering the problem, are likely the farthest along the road to self-discovery than anyone else you have a reasonable chance of meeting. To find someone else who's even
aware that they have the problem may be uncommon, but to find someone who can help you reach a solution could easily never happen. Or at least, they could be so rare that you could just conclude that it's a unique problem when it's really not. Of course you may be able to read into their answers and realize they're dealing with the same thing before they know it themselves... but in the end they still can't offer any substantive help.
Basically... the only realistic benefit I can see of discerning whether other people experience the same problem is the companionship in the face of a still mysterious problem which you yourself are probably better equipped to finding the answer to anyway. I won't deny the usefulness in companionship... but I doubt that's your main goal in asking people these oblique questions and I really don't think it will help you very much in reaching a solution by the methods of logic, introspection, and shared experiences either. A greater understanding to the problem, definitely... even if your mind is the best equipped to search for a solution, adding other peoples' experiences will provide it material to work with (assuming its a common issue)... but to a solution? Besides, now that I've "called you out on it" you know I've been thinking about the same kind of thing... so there's your companionship.
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Anything you can think of or have found on the subject I'll try my hardest to check my religion at the door and try to sort through with you... but I can't promise to be completely unbiased.
I hate to keep sounding pessimistic by the way... but I'm pretty much convinced that this is going to be a very long, painful search for as long as you go about it. In fact if you find some way to define the root of the problem clearly and find a solution that you can succeed doing with pure effort and we're out of contact, please, hunt me down and explain it to me--I'll have to rethink my worldview pretty significantly. Until then I'll just try to help out the best I can.