So, recently I have found myself missing the way Martha fandom used to be. Mainly because, by having all the companions around simultaneously, The Stolen Earth completely proved to me that it's Martha that makes me the most squeeful. And, without even really trying, I have found myself expending a lot of mental energy on trying to work out who is to blame for the fact that it isn't that way any more. Was it RTD for making the choices he did? Was it the people who set expectations the show could never meet? Was it the people who couldn't cope with anything other than squee? Was it the people who weren't happy making inappropriate choices of venue? (I'm not even sure which of those categories I fall into. Well, except that I know I'm not RTD.)
And then, just now, it hit me: it's not actually anyone's fault. It's a natural part of the life cycle of such a thing. A large group of people come together united by some particular thing they like and have fun together based on that. But people change, and if the thing they like is itself changing as well, then there's going to be a drifting apart. It will turn out that the aspect of the thing that this group over here liked was not at all the same aspect as this group over here, and so some will continue to be satisfied and others won't. Looking over fandoms I'm familiar with, it seems to happen everywhere: Buffy fandom was only really united up 'til Becoming, AFAICS, and became more and more fragmented for more and more diverse reasons with every season after.
And the thing is, it's natural to want everyone to be happy. But eventually some people are going to become unhappy, and if they can't understand why the people who are still happy are still happy, then they're going to be even less happy. (This was a particularly big problem for Martha fandom, because of the specific issues involved.) And if it all ends up in an argument, then everyone's unhappy. But it's still not really anyone's fault. At the heart of it all, everyone secretly wishes it could be like it used to be.
But that's not going to happen. I think large, active fandoms are transient phenomena, with their lifespans mainly affected by the pace of events in the source material and their size (the larger they are the more transient, because it is people are going to start drifting off -- it's like radioactive decay or something). The Martha fandom of S3 was never going to last, and instead of wishing we could get it back I think it's better to celebrate what we had. Which was an enormous amount of fun. And the basis for many individuals getting to know each other better (I can think of several of my favourite flisters who I met through Martha fandom). But it was never going to last, and we don't have to beat ourselves up for that fact.
TL;DR: we'll always have The Drabbles of Awesome.
ETA: Courtesy of who_anon, that Buddy Holly Ten/Martha vid by nostalgia_lj that never fails to make me jump up and down with squee.