In an interview to Elle UK magazine, the 26-year-old "Cafe Society" actress has gushed about her on-off girlfriend, Cargile.
"Right now I am just really in love with my girlfriend. We've broken up a couple of times and gotten back together, and this time I was like, 'Finally, I can feel again.'"
Stewart, who dated her "Twilight" co-star Robert Pattinson from 2009 to 2013, said dating a girl has completely changed her life and made her even more happy.
"But then it changed when I started dating a girl. I was like, 'Actually, to hide this provides the implication that I'm not down with it or I'm ashamed of it, so I had to alter how I approached being in public. It opened my life up and I'm so much happier," she said.
Stewart previously dated French actress and musician Soko for a short period before calling it off in May this year.