The Skyscraper singer endured a stint in rehab in 2010 to tackle a number of issues including drug and alcohol problems, as well as bulimia and bipolar disorder, and she has since sobered up and got her career back on track.

Lovato paid tribute to her manager Phil MCIntyre as he helped her launch her new record label project with pal Nick Jonas this week (beg25May15), and she credited him with pulling her through the most difficult time of her life.

In a lengthy message posted on, she writes, "Phil MCIntyre. This man not only believed in me when I was 15 and made my entire career happen, but he fought so f**king hard to get me sober. When so many others had given up on me, he never did. He told me he cared too much about me to watch me self-destruct... Therefore at the very end of my drinking and using he gave me one last chance... Get sober and he'll stay, or he'd have to leave. He did that out of love... He stood his ground and said 'If you do this (get clean) I will fight this battle with you every step of the way'...

"He is one of the very few people who LITERALLY saved. my. life. (sic) I don't think I'd be alive without him for many different reasons... He'll never take the credit either yet he deserves ALL the credit IN THE WORLD... Phil is one of the most HUMBLE and hard working people I know. I can't wait for our future together Phil. I'm SO GRATEFUL FOR YOU!!! Love you SO f**king much."