(Cover) - EN Showbiz - Demi Lovato has called her rehab stint the darkest time shes been through in her life.

The 18-year-old Disney star checked into a treatment facility at the beginning of November last year, causing her to pull out of her tour with the Jonas Brothers.

The reason she sought help has not been revealed, with her spokesperson only saying she was receiving care for emotional and physical issues. There was speculation she may have been struggling to cope with her hectic schedule.

Demi checked out of the undisclosed rehab centre in January, and has posted a video online to reassure fans she is feeling better. I wanted to let you know that I am back and home, she says in the message. I wouldn't be here today if it wasn't for the support you guys have given me along the way... Your support is what got me through this.

I can't tell you how much light you guys brought into my life in probably the darkest time of my life. Without you guys, I wouldn't be here today.

Demi didnt talk about why she needed help, only saying she has the same issues as many young girls her age. The star has spoken about her struggle with bullying in the past, and there has previously been speculation she has harmed herself. She was pictured with angry red marks on her wrist several times in 2008, but her spokesperson was quick to shoot down rumours the marks were the result of cutting.

The journey that I've been on has been very difficult over the past few months. I was dealing with issues that I know not only girls just my age but of all ages are dealing with, she added in the video. (C) Cover Media