The 40-year-old actress believes her early success, including winning an Academy Award in 1998, made people wary of her and revealed as she gets older she finds herself surrounded by more female friends including celebrities Cameron Diaz, Beyonce Knowles and Stella McCartney.She told Self magazine: "I feel a sisterhood emerging around me. I'm less threatening now that I'm 40 and not 26-with-an-Oscar. "They know I've been through a lot of pain and suffering - some public, some private - and I keep going. Or maybe it's just that I was the first one who could afford therapy!"Beyonce, 31, who has a 14-month-old daughter Blue Ivy, previously revealed she is grateful to count the 'Iron Man' actress, who is raising daughter Apple, eight, and son Moses, six, among her best pals because they both understand the demands of managing a high profile career and motherhood.She said: "She is incredible. She's a great friend on every level. I think for us, protecting our daughters is so important and ... keeping things on our own terms, so I will still be protective and make sure [Blue Ivy] has a childhood and a great time."