The Skyscraper hitmaker sought treatment over a year ago for 'emotional and physical issues.'
And although she tries to remain positive, the last year has taught her some tough lessons.
The 19-year-old says she's much more guarded with people she meets these days.
Lovato told Parade.com: 'Just to be careful who you trust. Sometimes you don't know who you can and cannot trust.
'I still learn that over and over again.'
The star also credited a better work-life balance for helping her in her recovery.
She added: 'I'm in a much happier and healthier place now, so I'll be able to decide when I need time off. It's a different era in my career. I'm sure that if I need time off I'll be able to speak about it and I'll take a step back.'