Having read extensively on this subject, I've come to the following conclusions:
The Floyd as a band started to disintegrate after the success of Dark Side Of The Moon. As Waters himself I think put it, "Once you've cracked it, it's all over." Anyway. Wish You Were Here is a clear indication that things were starting to get tricky, with an apparent atmos in the studio of "nobody really looking anyone else in the eye". Animals is the breaking point really though. Rick Wright (RIP) was struggling with a drug habit and not really pulling his weight it seems, and by this time Mason may have just settled in for the ride. Gilmour & Waters were both still fully engaged I'd say, but starting to pull in different directions.
From there it was pretty much inevitable. True, Waters started to push out other people's material, but I think it wasn't just egomania - in his own way I think he was trying to keep quality control high. Having listened to both Gilmour & Wright's solo albums from 78, probably only a few songs might have made it onto a Floyd album even if Waters had been more accomodating.
The Wall settled it. Again, Waters probably felt he was carrying the lot of them by then. They lost enormous amounts of money through bad investments and were facing a huge tax bill and possible bankcruptcy it seems, and their next album had to be a big seller or else. Waters was the only one to come up with much material it seems and if he ranted a bit to get his own way, I'd say history favours him on this - the album made millions and saved their bacon without selling out (really, it was a risky album to realise when you need to make money).
After that he was always going to be top dog or nothing, really. In a way, can you blame him? After all, the final two Pink Floyd albums are nice, brilliant in places, but they do lack the emotional punch Waters carries with him.
Finally, I'd just like to say that if you grew up without a father figure, I'd say that qualifies you as being allowed to have a whinge. Doesn't seem to have done too much harm to Eminem's career either. In a way, it's better to have a whinge than to keep it all in and end up a loose cannon like Raoul Moat.
Do you know, I may have kicked something off here!