The Almost Famous beauty, 36, is mother to two boys, 12-year-old son Ryder with ex-husband Chris Robinson and four-year-old son Bingham, with former fiance Matt Bellamy.

But in a new piece for InStyle magazine titled Sometimes I Feel Like a Bad Mom, Kate admits her role as mother hasn't always been easy or normal.

"I was really young, like, 23, when I had Ryder. So, our relationship has always been a little unusual," Kate tells the magazine. "I mean, we're close, and I am his mom. I'm big on manners. I'm big on politeness. I'm big on gratitude. But I'm a bit of a wild mom.

"Some days I feel like I should win best mom of the day award, and some days I find myself doing strange things that don't have any real purpose, in faraway corners in my house, and I realize I am literally and deliberately hiding from my children."

She continues, "Even as I write this, I am traveling for a week away from my children to promote my book, Pretty Happy, and I'm so happy to have some time to myself and excited to have this experience. But there's this tight, pulling sensation that never goes away that it comes at the cost of missing a week of my children's lives, and it aches.

"But I wouldn't be the best mom I could be if I didn't follow my creative endeavors. I would feel an emptiness that would be felt in our home. So a stay-at-home mom will never be my life and that will never be my kids' experience of me."