Hi Schultzy! I have a couple ideas that might work for you. First off, the Nalgene wide mouth bottles are good for winter. Second, OR makes insulated sleeve containers that the Nalgene bottles fit perfectly into. Third, sleep with your water bottles with you inside your sleeping bag. You can put them in the foot area or by your waist. Sometimes I wrap them up in other clothing and use them for a pillow, but need lots of clothing or they hurt your head.

I found out the hard way during one of my first winter camping trips. I left the water bottle outside the sleeping bag next to me, so I could drink at will, and it froze and the bottle broke. I was bummed. But luckily I had a couple more bottles to use.

If you're climbing or camping on a mountain and you've packed in, you will want to monitor using your gas. You don't want to run out of gas and have another day of food and snow to melt.

Water bladders are good too, but you have to be careful with the hose. It freezes where it is exposed to the air (from your backpack to your mouth). Even hiking during the day in the sun, the hose can freeze. Camelback or MSR makes a hose insulation tube. You disconnect the hose and feed it into the tube. Works great. Again though, the bladder would have to be wrapped in clothing and kept inside your sleeping bag. I tried a bladder once in winter and the hose froze. So I decided to keep it for late spring, summer and early fall and use Nagene wide mouth water bottles for winter.

Have fun, winter camping is great fun. I love it!
Cheers!
Patty