Russell Brand with Katy Perry.
"I thought to myself, 'When I find that person that's going to be my life partner, I won't ever have to choose between the partner and my career. They won't be threatened or have weird motives. Then I started to realise, that's not true," Perry said in the video of her new documentary film Katy Perry: Part of Me.
The 27-year-old says she did everything in her power to save her marriage, before finally acknowledging it was over.
"I have that same belief system with everything, from career to my life to my personal life, everything. And I will do everything it takes to not fail. And I did everything it took, but it still failed," she added.