AceShowbiz - Rocker Dan Reynolds turned on his Mormon roots when he was kicked out of college for having sex with his girlfriend of four years.

The Imagine Dragons star admits he had always been the black sheep of his family for questioning his beliefs, and the "shame" and "guilt" he felt after he was asked to leave BYU in Utah really was the last straw.

He started looking more closely at the church's laws and rules and decided to test them by forming a rock band and then fighting for the rights of young gay Mormons.

Dan has since created a festival for gay youths and he's now winning acclaim for his new documentary, Believer, which tackled the stigma surrounding Mormons who want to be a part of the LGBTQ community.

"(Getting kicked out of college) was the first time I felt conflicted, where my heart and my mind didn't align," he tells lesbian talk show host Ellen DeGeneres. "I was like, 'Why is this thing that feels right gets me kicked out of college and shames me in my community and made me feel all this guilt?'. That's when I first thought something needs to change.

"I grew up and I had a lot of friends who were gay and Mormon, who couldn't come out to their parents; they couldn't even come out to me, because they just couldn't talk about it... Watching their struggle, for me, was awful, and then feeling a bit of shame in my life over something I shouldn't have been shamed about helped me identify, to some degree, with what our LGBT youth were going through".

Reynolds reveals his therapist told him to "live my truth", which sparked his interest in helping the LGBTQ Mormons, caught up in the struggle to come out.

"He told me, 'You need to offend people sometimes; you have to speak your truth. If you don't you're just kind of suffocating...'," the rocker, who considers himself "a unique Mormon", explains.