Jennifer Aniston has had more fun since she turned 40.

The 'We're The Millers' star - now 45 - said she has been in a much better place since hitting the milestone, which is something she credits to her career, friends, and relationship with fiancé Justin Theroux.

She admitted: ''I've had more fun post-40 than I can remember,

''From a work point of view, a physical point of view, a psychotherapeutic point of view.''

The actress was previously married to fellow actor Brad Pitt for five years until their separation in 2005, and confessed that she found it difficult to bounce back from the split and find romance again, which led to her having a break from dating before meeting her 43-year-old beau.

Speaking of the time on her own, she explained: ''It really helped me get to a place where I was more comfortable with myself, truly ready for love and for a partner.''

''The past wasn't 'less than.' It was extremely important to my growth as a woman. But if you take the law of attraction, if you only love yourself 70 percent, that's what's going to come back to you.

Jennifer - who was in London on Wednesday (12.11.14) for the world premiere of her new movie 'Horrible Bosses 2' - added that she was drawn to her lover because he is so talented yet doesn't brag about his skills.

Talking to Harper's Bazaar magazine, she said: ''Not only is he a great actor but he's one of the best comedy writers out there. And he directs and paints murals.

''And I just think it's so attractive to be that good at so many things and to have no ego. He's one of the most humble, decent human beings. He's not an ass.''