The only time I really get stressed is in the winter..
Driving in snow, ice, blizzards..
Well, I also get stressed sometimes in storms. We sometimes have some wicked thunderstorms.
I also get stressed when I'm running late (having to wait on my daytime driver to get back etc)
Perhaps I get stressed about things other than winter.
What might help with stress:
Stop at a truck stop, and take some time browsing.
Getting a cup of coffee, and visiting with other drivers.
It also helps if you have satellite radio.
If you are up in the Dakota's, you might stop at a tourist spot. Go look at western memorabilia. You know, those jip joints that have a rifle, or pistol from every outlaw that ever packed an iron.
Sometimes it helps just to pull over and smell the flowers and get a bowl of rainbow stew...