I've been told that Japanese culture is very "strange" compared to US culture in regards to relationships with other people. What is it specifically though that makes it so hard to make friends over there?
I wonder how much of it was the company, and how much is Japan. My wife's workplace has its own problems, but is a more lively and communicative place than the game company I was at... that just seems /wrong/.
In the workplace, at least the one I was in, there was very little socializing; in other companies, afterwork gatherings are apparently common, or were common until The Bubble burst, but that was a long time ago. Also, there was little verbal communication in general. It was indirectly discouraged, which had a ripple effect through the company's culture.
As far as what's different between Japan and the USA, I'm sure books have been written on the topic, but I'd summarize it by saying that it is hard to get past initial barriers with Japanese, but once in their confidence, trust is very high. In contrast, it is easy to know quite a bit and be rather friendly with Americans without ever really gaining their trust.