The Ugly Truth star has said that when she and Kelley began to court one another, Heigl was the initiator and aggressor.
Heigl told Now magazine: "I didn’t wait for him to call me, I thought, 'Screw it, I’m going to call him!'
"I invited him to a friend’s barbecue and it was on from there. He played it really cool. He says now that he wasn’t trying to, that’s just how he is - which is bulls**t!"
She added: "I had to fight for him to like me as much as I liked him. If you have a guy who’s like a puppy dog at your feet, then it’s not as sexy and interesting as the guy who plays it cool. Sometimes it’s about risking it.
"It gets lonely, scary and weird out there, so I love being able to go home to him."
The Ugly Truth is currently in cinemas.