I have resorted to wearing three pairs of wool socks. I have to go a size larger boot than I normally wear but that works better for me since the larger boots keep my toes from jamming the end on serious downhill stuff. The outer portion of boots get wet in snow, and once wet, there is no breathability. Some boots breath when dry, but not when wet. I also carry spare socks and swap out daily or sooner if needed. I use "hot hands" to dry out socks at night in the sleeping bag. Putting a "hot hands" packet in the outer layer (third layer) sock at night feels great and also dries out all three layers by morning.
