What has Demi Lovato got to be depressed about?

Urgh i just get annoyed by people who have perfectly good lives who get depressed over anything. shes 18, living the life of millions and millions of people can only dream about, she looks stunning, has an incredible voice, probably earning a **** tonne, but she hates her life? What gives? There are millions of people who don't have anything at all and get on with life perfectly fine. and she cries about having to pick over gucci or prada >.>