Lonely in Sanity

Surrounded by people,
I am alone;
Surrounded by water,yet I cannot drink;
To be sane is to know yourself,
Stuck in my head I am free.

I walk amonst the sinners and saints,
Each their own god and each their devil
Their life magnified by round reflective mirrors,
But who's to say that mine is see-through?
Clear as day's first's rays or foggy as morning mist.