She said: "He's the greatest human being I've ever met. He really is, and he gets better ... I started with the basics. 'How do I feel? Is he nice? Is he kind?' It's just - this is the one, I know that sounds really stupid but he's just, he's - you know. He's the greatest person I've ever met.
"I wasn't at a place where I was like, 'I'm ready to get married.' I just met Cooke and I wanted to marry him. We wanted to marry each other, we wanted to commit fully. He's my best friend, so I want to legally bind him to me forever. Fortunately, the paperwork exists for such a thing. It's the greatest. You find your favourite person on the planet, you're like: You can't leave."
The 'American Hustle' actress isn't feeling nervous about her big day because she's so "lazy" and she's already found both her dress and wedding venue.
She added: "I've been in a good place. I haven't been neurotic about it. I'm like too lazy to be neurotic. I saw a dress I liked and I was like, 'That's the dress.' I saw a venue and I was like, 'Cool, we got the venue.' "
Jennifer previously dated Nicholas Hoult for four years and also enjoyed brief romances with director Darren Aronofsky and Coldplay's Chris Martin.
- BANG Showbiz