...
Furthermore: greed had gotten the better of me at times (during 2012 and 2013 mainly) and I saw people increase their BTC-stash by large percentages by selling high and buying low, so I tried that in order to acquire more BTC. I failed miserably because the market got away from me repeatedly. The attempt failed more often than not (it was mostly a bull market after all, so what do you expect given a non-experienced trader like me). Those experiences stuck with me and I have decided that holding is the best strategy for me (and selling a little bit for fiat/metal at times in order to not have to hear "see, I told you so, you should've sold" from friends and also of course because of fear).
Also: I think I'm quite a bit more relaxed than you picture the average hodler to be: Bitcoin could go to 0 and I'd still have a good life after that. I'd be quite sad and angry for a while for sure (depending on the circumstances, of course), but I'd be able to get on with my life, both financially and psychologically.
...
This is critical in understanding the psychology of the holder. Greed and fear are reversed. Bitcoin becomes "the money" and fiat "the investment". Selling is actually driven by greed and not fear since it is done with the objective of actually acquiring more bitcoin by engaging in a buy fiat low sell fiat high strategy that more often than not can fail.