Katy Perry was desperate to save marriage to Russell Brand

Katy Perry was so desperate to save her marriage to Russell Brand, she flew all over the world to see her husband while she was on tour and ended up battling exhaustion.

The British funnyman split from the pop star late last year (11) after just 14 months of marriage and Perry documents the weeks leading up to the break-up in her new movie Katy Perry: Part Of Me.

Candid footage shows the singer sobbing backstage as she struggles with her marital problems and she reveals she made massive efforts to keep the relationship alive by flying to see Brand every two weeks throughout her 2011 tour.

In one emotional scene, Perry appears to blame her husband by accusing him of failing to make similar efforts to visit her. When a crew member asks when her partner is coming to visit, Perry angrily responds, "He should but he's not," later admitting, "I'm fighting to keep my marriage alive".

In another scene, shot shortly after the couple split, Perry explains, "I'm a romantic and I believe in the whole fairy tale. Love is a dream but the reality is making it work. I did everything I could - but it's still failed."

Speaking about the documentary, she tells Britain's Radio Times magazine, "Every 10 days or so I would put everybody (on the tour) on pause for three or four days so I could go back and re-charge and see to my relationship and give that time, which was very intense for me because the show was still on the road.

"But I made that sacrifice because it was important for me and I had made a commitment at that time. Sometimes I had to fly in on the day of the show, completely jet-lagged and feeling like I had been hung by my ankles, and have to go on stage. But it's like I pushed a button when I walked out (on stage)."