AceShowbiz -

Selena Gomez's mom believed that the singer's ex-boyfriend Justin Bieber was partly to blame for her most recent rehab stint. Mandy thought the Canadian heartthrob was a bad influence on her daughter, so she personally asked him to cut all ties with the former Disney darling after she left rehabilitation center last year.

According to Life & Style, Mandy called Justin a few months ago and urged the "poisonous" pop star not to call, text, email or see Selena. "[Selena's] family feels that no one has ever gotten under her skin like Justin and, ultimately, he affected her in a deeply negative way," a source tells the news outlet. "[She] really believes that Selena will be able to heal faster without him."

Selena canceled her tour last year before checking into a rehab facility due to anxiety, panic attacks and depression caused by lupus. The same publication said last month that Justin was another reason behind her downward spiral. A source said at the time that her obsession with the 22-year-old singer affected her health.

"Her addiction to Justin is what everyone is afraid is going to take the ultimate toll," the source explained. "Justin takes her to a dark place mentally, and she really can't let go. She was stalking Justin on social media."

"She became a different person around him. She was extremely jealous and possessive and felt like she had to keep up with him to keep him. So she would drink and smoke, and then she got into weed and partying," the source added.

Selena's much better now. She made her first public appearance since the rehab stint back in November, when attending the 2016 American Music Awards. She delivered a moving speech after receiving the Favorite Female Artist - Pop/Rock Award at the event.

Also, she has apparently moved on from Justin with The Weeknd now. The two were spotted making out after grabbing dinner together at Italian restaurant Giorgio Baldi in Santa Monica earlier this week.