Scarlett Johansson thinks it's hard for actors and actresses to enjoy successful marriages.

Scarlett Johansson

Scarlett Johansson

The 30-year-old beauty, who recently starred in 'The Avengers: Age of Ultron', was married to fellow Hollywood star Ryan Reynolds from 2008 until 2011 and Scarlett's admitted that it's tough for two people who exist within the acting bubble to maintain a healthy relationship over a lengthy period of time.

The actress - who married Romain Dauriac last year - told Parade magazine: "Acting is a very strange world to be co-existing in. It's very volatile.

"There's always going to be the more successful person. It's related to rejection. Because actors, if they're not having success, connect it directly to unpopularity - to the fact that nobody wants them."

This comes shortly after one of Scarlett's ex-boyfriends, Josh Harnett, confessed some of his famous ex-girlfriends were "mistakes."

Josh - who has been in a relationship with British actress Tamsin Egerton for the last two years - shared: "I've met very important people in my life doing films. Sometimes that had consequences that were just awful for everybody involved. Some were fantastic all the way through. Everybody makes mistakes dating people they work with."