The 23-year-old model and actress started dating her singer love, real name Annie Clark, around 16 months ago, and the pair recently sparked rumours they might be engaged.

Now Cara has opened up about her relationship in the September issue of Vogue magazine, admitting her girlfriend is responsible for showing her just how deep love can be.

"I'm completely in love..." Cara told the publication. "Before, I didn't know what love was - real love. I didn't understand the depth of it. I always used to think it was you against the world.

"Now I know the meaning of life is love. Whether that's for yourself or for the world or your partner."

Prior to her relationship with St. Vincent, Cara was romantically linked to male celebrities including singer Jake Bugg and One Direction's Harry Styles.

However, Cara refused to define her sexuality when asked in the interview, insisting she is "liquid".

"As a child I used gay as a bad word, as in, 'That's so gay'," Cara added. "All my friends did. I'm obviously in love, so if people want to say I'm gay, that's great. But we're all liquid - we change, we grow."

Cara initially found fame as a model before transitioning into acting. She can soon be seen as Enchantress in Suicide Squad, but admits she has a lot to learn about her new industry.

"I'm still learning. I act for love," she said. "I give it my all. I would probably still do it even if I wasn't paid at all."

Despite this comment, Cara was quick to clarify that she would only accept no payment if her male co-star did the same. Referring to the debate surrounding gender equality in Hollywood right now, Cara added: "In terms of equal pay I need to be paid the same as the guy who has equal billing with me. Otherwise I won't do it. Because if you accept less, you're just letting everyone else down and continuing the cycle."