The singer and former Disney star told fans “This has already been the longest October of my life” just a couple of days into the month.
She also posted a picture of a neon sign that read “Good vibes only”.
The 28-year-old hasn’t had an easy time lately.
Demi, who has been open about her past struggles with addiction and mental health, dramatically split from actor Max not long after they’d got engaged.
It comes after Max sensationally claimed that she had used him in a “calculated PR stunt”.