Treadmill vs. Pavement

I do both, When I started I did Treadmill 100% of the time, then I tried to do an outdoor 10k on pavement in the wind on a rainy day... "WTF is wrong with me and why do my legs feel like they are on fire" was my thought about 4k into it.. So now I only do the treadmill if I have to (Major thunderstorm, hail, uber ice etc.) keep the incline at 2% minimum and keep the pace do able but on the cusp of uncomfortable. I make sure I keep looking outside to see, Hmm is it really that bad out ?? Like everyone said Try and do your long run outside, get a running buddy, drive to a park, run a school track, or come up to Canada and I'll run with yha !! Cheer's