The "One Big Happy" star admitted her romance, which ended in the pair calling off their engagement earlier in January, was "unhealthy" and she found herself turning into someone she didn't want to be.
"I wasn't myself. It wasn't me. Everyone was like, 'What are you doing?' and I was like, 'I don't know'. I lost sight of what was the right thing, what was the wrong thing. I got caught up in something unhealthy and toxic. I'm so glad that it is so far away from me now," Brook said.
The 35-year-old said that she wasn't "in control" of her life when she was with the "Gladiators" star and felt as though she was being betrayed on a "daily basis".
She added, "Back then, I wasn't in control of what was happening in my life. A lot of my family were really upset for me but I couldn't do anything about it. I couldn't control what was happening.
"When you put all your trust into something and it's betraying you on a daily basis, it's confusing. Now I don't have that any more so of course I'm going to be happier," asserted Kelly Brook.