The singer, who appeared downcast when she returned to work on Wednesday, said she is "devastated" by the break-up, reported Sun online.
"I'm devastated that it didn't work out. It was the hardest decision we had to make, but we made it together," she said.
Despite this being the fourth time that they have split, Scherzinger, 36, maintained that they still love each other.
"I love Lewis and I know he loves me. We wish nothing but happiness and the very best for one another. I'm trying to stay strong in my faith right now," she added.