I have Moon and north node in the 12th house, and needing my 'alone' time is putting it mildly! I am an introvert and spend most of my time alone. Hey, wasn't it that famous old movie actress who always said 'dahling, I vant to be alone!' Yep, she had 12th house stuff for sure. 12th house planets cannot tell the whole story, since I have mars in pisces in 8 and jup in pisces too. There are some very outgoing 12th house people. Think of George W for instance! yikes.
barb