The 38-year-old, whose birthday is in August, said, 'There's nothing scary about it at all.
'Life is so much better as you get older.
'You're liberated from so many things.
'I feel stronger, better, more capable, more fulfilled, and happier than I ever did when I was 29, when I was 30, even 35.
'I prefer it.'
The Bad Teacher star also insisted the 'dry humping' scene in the new comedy with her ex, Justin Timberlake, would have been more awkward if they hadn't ever been a couple.
'It's much more awkward when you don't know each other,' she said.
Talking about how she and Justin are now friends, she added, 'We had a relationship that was different to this part of our relationship and if we held onto things that everyone would assume that we should be holding onto, we'd just be missing out on the friendship that we have now, and there's no reason for that.'