Everything familliar is normal to us. Our bodies, our demeanor, social structures, and the things we've inserted into our environs all affect the surroundings with which we coexist on both a physical and spiritual level. And unless done so with great care, we may be surprised to find we've created what we've created.
We get so accustomed to the things in our life -- whether they're good or not -- that we don't see them for what they are. It's why people behave terribly or not, why cars run on gas or not, why we get fat or not, etc. Sooner or later, if we don't take a fresh, "lets-pretend-its-not-normal" look at things, we may be surprised that our entire world -- physically, socially, and spiritually -- has become a terrible mess.