RAM problem (8 gigs) (Fallout 4)

Hello everyone, if the topic has already been, I apologize, dig into the bastard at night)
In general, the essence of the problem: at the beginning of the game I sat calmly, played for more than 3 days in the game, opened most of the locations, just got into Diamond City, everything is fine, no lags, no crashes.
But recently I started to notice jams, after a while an error flies on the desktop, they say, there is not enough RAM in order to avoid data loss, close the Fallout 4 application, it was not there before, the beginning appears after arriving closer to the "Constitution" location (flying ship ) after that it began to appear everywhere, after some time in the game.
8 gigs of operatives, 2 gig gtx 660, no overheating, no swap file, I release the RAM before the game (close antiviruses, etc.) is it possible to somehow solve this problem? no if it just swore that there is not enough memory, but after a while the game just crashes to the desktop without errors, when you press ESC or when you open a pip-boy.
Thank you in advance for your response)