Story involving young female space travelling escapee with multiple personalities

I'm looking for a story about a youthful (late teens?) female protagonist who begins the story by making an emergency escape from an orbital habitat. The protagonist is actually host to multiple disassociated (as many as seven?) identities, of whom she is initially unaware. They are capable of holding council internally, however.

Another spoiler-free notable story piece is a race of aliens who mark their 'naturally present' personalities/identities with a glyph or character on their bodies before venturing into public spaces.

FTL in this story must be performed by a non-human pilot, while the remainder of the occupants are either put to sleep or in suspended animation (I don't recall), due to eldritch somethings in the great beyond that will drive human pilots mad.

I believe it was written in either in the late nineties or early aughts.