You can pick one of the three, do it yourself, let the girl do it or do it yourself, either way the game ends there, but if you get the DLC it starts up again and theres loads to do, i havent done EVERYTHING till this day even after playing it for over 100 hours
Again, get the DLC
lol if you see a deathclaw before it see's you, SAVE, it took me about 8 attempts to get to a certain place past 3 deathclaws, one can kill you with about 5 or 6 strikes, im on level 12 atm
Definately worth it, the hardcore mode makes it more difficult/interesting, finding water is a bitch lol and of course the stimpacks not being instant makes it a whole different ball park