Mary Jo Eustace, the ex-wife of TV actor Dean McDermott, discussed learning the painful news that her husband was leaving her for actress Tori Spelling on Good Morning America Tuesday.
Eustace said that McDermott, who divorced her and married Spelling in 2006, had come in from a golf game and told his then-wife that he had bedded the 90210 alum, and that he felt Spelling was his "soul-mate" who loved him "unconditionally."
Canada native Eustace -- who authored a book about her experiences, titled Divorce Sucks -- said that McDermott refused to let her leave the country with the kids unless she met Spelling (who later admitted in her own memoirs she had a knife inside her purse).
"I had to meet the other woman," she said of the three-hour meeting.
Eustace said that on that day, she told Spelling how she disapproved of her behavior, but at the same time, stayed in Spelling's good graces so McDermott would permit her to leave the country.
Eustace said that things are cordial between her and her ex, three years removed from the split.
"I'm always civil for my son Jack," Eustace said. "My son is the light of my life."
The book, Divorce Sucks, is in stores now. You can read an excerpt at GMA.