Carol Hanisch's phrase, "The personal is political," evolved from a series of discussions in which people were writing memos to one another defending their positions on the worth of "bitch sessions" -- what would become known as consciousness raising.
It's worth a read -- as is a book review by Katha Pollit where she uncovered the history of the phrase and how it quickly lost Hanisch's original meaning. For Hanisch, to say that something personal was political was to demand that we recognize that, say, when your pscyhologist tells you that you need to work on the fact that you can't have vaginal orgasms or when some guy tells you to smile, it isn't necessarily your personal problem, but can be seen as an event that emerges from systematic processes in society. More, that, as Hanisch says, "there are no personal solutions at this time." By which she meant, the problems women face, seemingly personal problems to be resolved by psychiatrists, pills, or getting a better attitude and smiling more often, but would only be changed through collective political action.
http://blog.pulpculture.org/2006/05/01/hanisch-new-intro-personal-political/