Motes, a dog walker and pet sitter, was last in the news in August after giving an interview about being bullied about her weight as a teenager by Roberts.
"When I was in high school and she was an adult, she would just let me know that I was definitely overweight," Motes said at the time.
"It just makes me feel incredibly hurt and very sad," added Motes, who once weighed nearly 300 pounds before her decision to undergo gastric bypass surgery in June 2010.
Motes was estranged from Roberts. She and her husband, a locations manager, were engaged to be married in May. According to the coroner, prescription and non-prescription drugs were found at the scene.
[image via AP]