Former Bachelor star Gia Allemand was on the phone with her mother when she hanged herself in her New Orleans apartment in mid-August, the latter revealed to Dr. Phil McGraw in a segment that aired Tuesday.

In the emotional interview, Donna Micheletti revealed the last moments of her daughter's life.

"I'm the closest person in the world to her and she didn't want to be alone when she left this world. So she wanted Mommy to be there, I guess," Micheletti said as a possible explanation for the phone call with the late 29-year-old. "It destroys me, but if it made her feel better, then that's fine. I don't mind dealing with this."

"I heard her last breath," Micheletti added, while also saying, "I'm really mad that she did this for no reason. In 12 hours it would have been fine. I'm really angry."

Gia Allemand Family PHOTOS With Mother, Brother & Sister

In their last phone call, Allemand told her mother she was unhappy and "I can't go on like this anymore." She wanted her mother to come to New Orleans to see her and give her a hug, Micheletti said she could tell her daughter had gone into "a dark spot," which she sometimes did when she was menstruating. She also said she tried several times to get Allemand to see therapists, but the former model would not go beyond one or two visits.

Allemand's unconscious body was found by her boyfriend, NBA player Ryan Anderson, 25, on Aug. 14. She was rushed to the hospital and put on life support, but died two days later.

McGraw also spoke to Jake Pavelka, whose season of The Bachelor Allemand appeared on.

"I've never lost anybody close to me," the reality star said while crying. "Gia really understood me. We got really close after the show. We had such a special relationship. I can't tell you how lucky I feel that I knew her, but I wish it was not for such a short time, because I've never met anybody like her."

"She truly is one of the most amazing friends I've ever had," Pavelka added.

Gia Allemand & Ryan Anderson PHOTOS

Micheletti told McGraw Allemand and her boyfriend had a fight on the day of her death.

Anderson told investigators that he and Allemand had argued through lunch on Aug. 12 "over her suspicions that he had been unfaithful to her," resulting in the athlete telling her, "I don't love you anymore," according to an incident report.

Anderson told police that he arrived at Allemand's house 20 minutes after receiving a frantic message from her mother. He found Allemand unconscious with a vacuum cleaner cord "wrapped around her neck many times."

Gia's Top 5 Moments on 'Bachelor' and 'Bachelor Pad' [VIDEOS] 

Anderson did not come on McGraw's show, though the host said his team reached out to the athlete.

He told his viewers, "Gia's boyfriend, Ryan, was not able to join us here today. We reached out to him and offered him an opportunity to be part of this tribute to Gia in any way that he felt comfortable. Ryan told us that he was not yet ready to speak publicly about his loss. We certainly understand and wish him the best." 

Tags: Gia Allemand