Naya Rivera thinks Lea Michele was good for Cory Monteith.

Naya Rivera

Naya Rivera

The 29-year-old actress admits to having never really got on with her 'Glee' co-star but is glad the 'Scream Queens' actress was able to be a "stable influence" for Cory until he tragically passed away in July 2013 at the age of 31.

She shared: "When Cory and Lea started dating, it was a total surprise. The more serious they got, the less Cory hung out with us and the more he seemed like a different person. One year he came back from the break between seasons super skinny.

"He said he'd been spending a lot of time at the gym and was trying to be responsible - not spending money all the time and buying crazy cars like he used to. My personal feelings for Lea aside, I knew that she wasn't a partier, so I felt like maybe their relationship could actually be good for him. I was happy for Cory to have a stable influence in his life, wherever it was he found it."

Meanwhile, Naya also opened up about her strained friendship with Lea, 30.

Writing in her new book, Sorry, Not Sorry: Dreams, Mistakes & Growing Up, she added: "One of the 'Glee' writers once said that Lea and I were like two sides of the same battery and that about sums us up. We are both strong willed and competitive - not just with each other but with everyone - and that's not a good mixture ...

"As the show progressed, though, that friendship started to break down, especially as Santana [her character] moved from a background character to one with bigger plot lines and more screen time. I think Rachel [Lea's character] - erm, I mean Lea - didn't like sharing the spotlight."