On Tuesday, Demi Lovato celebrated an important anniversary – her sobriety. The “Confident” singer, 23, took to Twitter to share that she was four years sober.

“This last year I experienced so much life and too much death… But I made it through… Sober. #4Years #GodsWill,” she tweeted.

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Two days before the anniversary, Lovato tweeted, “I can’t believe I have 4 years on Tuesday.. Anything is possible.”

It’s been a year of extreme highs and extreme lows for Lovato, who released her album, "Confident," this past fall to rave reviews. But the singer also suffered the loss of several family members and friends in addition to the deaths of two of her beloved dogs.

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At the start of 2016, Lovato paid tribute to those lost loved ones on Instagram, writing, “I learned that no matter how painful things can be, things do get easier and time really does help heal all wounds. I'm so blessed to live the life I do, with the people I love by my side.”

The Disney alum has been an outspoken mental health advocate, candidly speaking about her addictions and struggles. In 2011, she entered rehab for substance abuse, bulimia, cutting and bi-polar disorder.