I don't know what's happening, now me too I'm getting thrown back to desktop from the game after 5 minutes of playing.
It started happening after the cultists found me on Solstheim.
I thought it was because I had updated to Nvidia driver dated 29/12 so I rolled back to the 2/12 one but still the problem remains.
Seems like a universal thing then.
Maybe it's the save file size again?
I took a look through my save files and mine is up to 16.4mb at the moment.
I can still play the game but it is unpredictable when they will happen or if they will happen.
EDIT:-
Played Skyrim for approx 3 hours and not one crash.
Could be one of these three things.
Changed Game Data load order.
Dawnguard
Hearthfire
Dragonborn
Other mods
Hearthfire was somewhere in the middle while Dragonborn was right down the bottom in amongst the community mods and my own.
Removed any mods which I was not using in game
Craftable Dragon Plate Crown
MacKom Lorestyle hairset
Rolled back to AMD driver 12.11 beta 11 with CAP 2