Nina Dobrev tried not to fall for boyfriend Ian Somerhalder

The Vampire Diaries actress Nina Dobrev initially fought the urge to develop feelings for her co-star and now-boyfriend Ian Somerhalder because she made a personal pledge to herself to keep it professional on set.

The 23 year old met Somerhalder when they were paired up on the hit TV series in 2009, and admits they shared an instant physical attraction.

But Dobrev refused to let herself fall for the hunk, so she could keep her job and her personal life separate.

In a new interview with Seventeen magazine, she says, "The first time I was on the cover of Seventeen, the cover line said: 'Nina: Why she wouldn't date any of her co-stars.' And then cut to two years later...

"It's funny that I said that, but you know what? It was honestly what I believed at the time. I didn't want to be dating one of my co-stars - my goal on the show was to be professional. But sometimes you can't help who you have a connection with, and you can only fight it for so long - which I did for a really, really long time."