So... I just finished Fallout 3.

Seriously... WTF???

I died and now I can do shit? This ending... ffs

I heard you had to buy the dlc to continue, but it isn't available on the ps store? I'm not planning to go out and buy the GOTY edition.

And why the hell didn't Fawkes go in there? Last time he went to get the greck because of the radiation, and now I die from radiation.

.... I'm pissed btw

Well then either try to get the DLC, no idea why you can't find it on PSN, or do the final mission at the very end of the whole game.
Pretty sure you got a note during the game that you can't go back once you progressed too far.

Never understood why people were mad about it. If the developer wants the game to end, then you have to accept it. A gamer doesn't have the right to play after the end, but be glad that there is the possibility of doing it with the DLC.

The worst thing of all is that you cannot send in the mutant, which is unharmed by radiation...!

I think it had more to do with the fact that the ending made no sense. Especially if you had Fawkes as a teammate, someone who is immune to radiation. He could have easily gone in the chamber and turned on the water purifier without anyone having to die. 

Obvioulsy, but as you said he's not required to do this mission. Would make even less sense to let you continue playing the game if you had Fawkes as a teammate, but not if you had someone else or no one at all in your party.

You die?!

...Did I even complete this game?

It's called, that was nice, reload your game.

Yeah, I ending sucks but at least the rest of the game is fantastic and if you really want a better ending then get the broken steel dlc it's alright.