The log that you provided is totally normal and shows that the game shutdown fine - is this a log immediately after your system rebooted? The logs cycle so its important that you copy the file before starting the game again.
Please can you provide the new player.log & player-prev.log after the reboot AND your le_graphicsmanager.ini file (game settings) and the output of a dxdiag report (system, drivers, diagnostics)
Cortana & Windows notifications have no impact on LE.
Some questions & checks:
What changed on your system at the beginning of the week?
Does your system Blue Screen or just restart?
Are you monitoring your system devices to try and see if there is some component failing? Are things like CPU/GPU/Temps/Harddrives etc as expected?
Have you looked at Windows View Reliability History to see if Windows is reporting any problems on your system?
Have you recently had a power problem? Has your power gone off unexpectedly? Could you have a problem with your power supply?
Have you opened your system to make sure that all the components are clean, fans working, nothing look like its loose or smell strange?
Is your WIndows installation up to date with all patches and relevant optional updates?
Is your GPU driver up to date and installed using a CLEAN installation?
Have you run the Steam Game File Verification option to make sure your game install is Ok?
Are you running any other applications while testing LE?