While she was filming the movie her marriage to British comedian Russell Brand was breaking down.
Perry said she included footage from that period because people already knew what had happened, and she hoped it might inspire others: "You don't have to lay down and die even if you feel like you're going to."
The singer added, "I think that people will relate to the movie even more seeing me at my lowest point and now at my highest point."
"Katy Perry: Part Of Me" is in movie theaters Thursday, July 5th 2012. Check Moviefone for local listings. "The Tonight Show" airs weeknights at 11:35 p.m. ET on NBC.
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