Katy Perry has opened up about her marriage breakdown, insisting she was determined to smile through the pain as her relationship with Russell Brand collapsed.

The I Kissed a Girl hitmaker wed funnyman Brand in India in October 2010 after a whirlwind romance, but they announced their split just 14 months later (Dec11) and filed for divorce earlier this year (12).

Perry has declined to discuss the break-up in detail but has now told how she covered up her sadness to perform for fans as her marriage fell apart.

She tells U.K. talk show host Graham Norton, "I love being on stage and even though I went through some pretty tough times last year I had to separate that because I know my problems are my problems and they are not the audience's problems. They are here to see a show and to be entertained, so I got on that lift, put a smile on my face and went up (on stage) with my t**s spinning!"