In the 1990s, the 57-year-old actress and her ex-husband Jude Law belonged to the so-called Primrose Hill set, a group of renowned people known for their love of partying.
Model Kate Moss, ex-Powder vocalist Pearl Lowe, her husband, Danny Goffey of Supergrass, ex-Oasis members Liam and Noel Gallagher, as well as their respective ex-wives Patsy Kensit and Meg Mathews, Lisa Moorish, Rhys Ifans, and Davinia Taylor, were all part of the friendship group.
However, Sadie maintains that today's youth are too preoccupied with social media to go out "making errors and learning as you go along."
"Everyone had a good time, and nobody felt bad about it," she claimed. London was fantastic, the music was fantastic, and the atmosphere was incredible and thrilling.
It wasn't created; everyone was just themselves. You were making mistakes and learning as you went, but now everyone is so afraid of status and "This has to be like this."
When asked if she ever believed that she and her friends belonged to the "cool set," she replied, "I don't think you know. Now, everyone evaluates someone's coolness based on their social media following and attention received. However, at the moment, it simply occurred.
From her previous union with Spandau Ballet singer Gary Kemp, Sadie has a son named Finlay, 32, as well as Rafferty, 26, Iris, 21, and Rudy, 20, with Jude.
The "Bram Stoker's Dracula" actress claims that although she enjoyed herself well in her youth, she also had to be "very disciplined" due to her children.
She continued, "I've always exercised, practised yoga, and been a vegetarian. I had a routine since I had to put the kids to bed every night. Although I've always been fairly diligent, I went out and had fun.
"I also miss my children when they were young. I long for a time machine so I could occasionally see the youngsters doing their homework while enjoying tea after school.
"I guess I filled the whole place with that loudness because I had all the kids. However, I have a true inner life and a creative life that may be quite solitary at times, and I realised I spend a lot of time by myself. Which, I believe, has something to do with ageing.