Delevingne, 22, has spoken about being "so happy" at the moment during an interview to Vogue magazine.
"Being in love with my girlfriend is a big part of why I'm feeling so happy with who I am these days. And for those words to come out of my mouth is actually a miracle," Delevingne said.
On being a child confused by her sexuality, the actress said, "It took me a long time to accept the idea of being attracted to women, until I first fell in love with a girl at 20 and recognised that I had to accept it.
On top of her modelling career, Delevingne is currently signed up for seven upcoming films, "The Face of an Angel", Michael Winterbottom's adaptation of the Amanda Knox story; "Kids in Love", a coming-of-age story set in London; "Tulip Fever", a period drama; 'London Fields", which is based on the Martin Amis novel; "Pan", a story about the origins of Peter Pan and Captain Hook; "Valerian", from Luc Besson; and "Paper Towns", adapted from John Green's novel.
But the actress has also revealed she won't be retiring completely from modelling, saying she "will do some more at some point.