mercurial
"Life is a roller coaster for those with the Mercurial personality style --- and they'll insist that you come along for the ride. From the peaks to the valleys, intensity imbues their every breath. Mercurial women and men yearn for experience... No other style is so ardent in its desire to connect with life and with other people" (Oldham & Morris p.293).
Sometimes I wonder if I'm just a typical Mercurial or if I sometimes slide into Borderline...