Entertainment Tonight ET Online ETOnline.com

Cesar Millan -- who became a TV star by utilizing his "dog whispering" skills -- has revealed that he reached such a low point in 2010 that he tried to commit suicide.

The 43-year-old reality star opens up about the the overdose that left him unconscious and hospitalized in a new documentary, Cesar Millan: The Real Story," which airs November 25 on Nat Geo Wild.

While promoting the documentary, Millan explained to the Associated Press that 2010 was a very rough year. In February of that year, he lost his beloved 16-year-old pit bull Daddy, whom he often used to help troubled dogs become more calm and submissive. In June 2010, Millan's wife of 16 years, Ilusion Millan, filed for divorce.

VIDEO: Dog Whisperer Takes On Kelsey's Troubled Pups

"I felt defeated, a big sense of guilt and failure... I was at the lowest level I had ever been emotionally and psychologically," Millan wrote in June on his official website, without specifically mentioning the overdose. He told the AP that after surviving the overdose, he opted for work, exercise and affection over antidepressants.

RELATED: Celebrity Suicide Attempts

In Cesar Millan: The Real Story, he does open up about the loss of his dog. "Daddy was my Tibet, my Himalaya, my Gouda, my Buddha, my source of calmness," Millan said. He also revealed that he's now met the woman he calls "the one," Jahira Dar, and plans to propose to her soon.

In addition to the documentary, Millan's seventh book, A Short Guide to a Happy Dog, is due out January 1. His new Nat Geo Wild show Leader of the Pack will premiere on January 5, after the conclusion of his previous show, Dog Whisperer.

VIDEO: How the Dogs Were Trained For Chihuahua 3