Speaking out for the first time about his former fiancée's suicide, actor and writer-producer Dean Cain tells PEOPLE that Mindy McCready was deeply troubled even 15 years ago, but it was her manipulations and lies – not substance abuse – that sank their future together back then.
"I'm saddened to hear of her passing, but I'm not surprised," says Cain, 46, whose starring role in TV's Lois & Clark ended just as he and McCready began their relationship in 1997.
They lived together and were engaged, but things imploded after a year. Cain struggled to remember any joy to their relationship: "I can't paint too pretty a picture. She would start arguments, start drama. Things weren't allowed to be good."
Though drugs and alcohol would later send McCready to rehab, Cain said neither was a factor in their relationship – or its demise.
"She was never abusive or addictive with me, but red flags were everywhere," he says. "I saw all the bad signs and told her to get out." At the end, he says he fled his own home for a hotel to escape her. "Everything she did was a manipulation of sorts. She would just get combative."
In the decade and a half that followed, Cain, who fathered a son with a subsequent girlfriend and is single today, severed all ties with McCready.
"When I did speak to her, truth didn't come out," he says. "She was kind of poisonous and not somebody I was going to have in my life anymore – or anywhere around my son."
Now, says Cain, he feels for the two boys McCready left behind.
"My first thought was of the poor kids. To think about the legacy those boys have been left, it's just tragic. ... All her troubles were self-inflicted. She had everything. She was a tremendous talent but everything about it was a waste."