Jennifer Aniston has said she believes it is “unrealistic” for people to think that relationships can last forever.

The actress, who was once married to Brad Pitt, said people who thought otherwise were “fooling” themselves.

In an interview with Cosmopolitan, Jen also revealed she was baffled as to why people were so interested in her life.

“It's so weird, even my dog Norman gets recognised - he's famous,” she said. “But I'm cutting him off, I've told him no more Oprah appearances!"

Jen has endured a series of high profile relationships since her split from Brad in 2005.

But, in a candid interview, the actress didn't appear to have hope that any of her romances would last forever.

"I don't think a perfect relationship exists. But I do think that many of us think it does and we're just fooling ourselves,” she said.

"Whoever said that everything has to be forever? That's unrealistic or hoping for too much. I don't think it's worth all that pressure."

Jen added that she believed the most important factor in any relationship was communication.

"People often expect their partner to read their minds, and when that doesn't happen, they get pretty upset,” she added.

“Then the other person gets even more upset and, at the end of the day, it's all because they didn't talk it over at the beginning."

Jennifer Aniston's life in love