@ginger: Never Play ICO, or Shadow of the Collosus.
Of course, in both cases you may find that you
don't feel alone. In spite of the, to be blunt, baffling stupidity of the AI companions in both game, the sheer sense of loneliness you otherwise have
does make you feel a very palpable sense of companionship.
It's one of the better things about the games, I find: Your character is tiny and weak and alone in a big, mean world, but you are handed a companion. They are weak and stupid and at times seem useless, but in spite of all that you love them anyways, because they're all you've got, and they do prove themselves useful every now and again.
In fact, I take back what I said. Play ICO and Shadow Of The colossus.