Harwick, 38, died of blunt force injuries to her head and torso after being transported to a hospital early Saturday morning, according to the Los Angeles County office, which described the incident as a homicide.
Harwick was found on the ground beneath a third-story balcony with injuries consistent with a fall after officers responded to her home at approximately 1:16 a.m., according to the Los Angeles Police Department.
Gareth Pursehouse was arrested later that afternoon and was being held in lieu of $2 million bail, the LAPD said.
Friend of murdered sex therapist Amie Harwick describes suspect as a 'stalker'
One of Harwick's friends said Pursehouse was "a stalker" who "didn't take it well at all" when the couple ended their previous relationship.
Harwick, who was once engaged to "The Price is Right" host Drew Carey, had a restraining order against Pursehouse until two weeks ago, when it expired, the LAPD said.