Your HDD can't keep up with the game. Buy a SSD or a faster HDD. I have the same problem sometimes, but the games sort of pauses until it's loaded again ;)

i got a bug i think i finished the diamond city blues pual left he was alive when i ended it and now his dughter keeps saying i killed him untill i first met her i didnt even new he was dead lol

i had the same glitch. happened when i got stuck in elevator and game wouldn't load,