Sober-friend
Contrary to your buddies who seem to only be fun or be more fun under the influence of alcohol/weed, sober-friends seem unbearable under the influence of alcohol/weed whether its because their tolerance is extremely low or they simply change for the worse.
"Man I smoked a bowl with my good friend Bob yesterday, and he didn't stop singing and telling me stupid highdeas. He will remain a sober-friend."