United Kingdom, Oct. 23 -- Demi Lovato feels a "responsibility" to share her troubles with her fans.

The 33-year-old pop star spent three months in rehab back in 2010, after being diagnosed with bipolar disorder and receiving treatment for bulimia, and Demi has now explained why she chose to be so candid about her struggles.

The singer - who once quit a tour with the Jonas Brothers after punching a back-up dancer - said on the Las Culturistas podcast: "I had a decision that had to be made when I had gone to treatment for the first time. I had this very public outburst when I was 18, which I talk about in some of my documentaries."

Demi recalled being given a choice of how to approach her struggles.

She said: "In that moment, my manage...