Nicole Kidman's romance with Keith Urban will be short-lived because of his drug demons, according to the country star's ex-fiancee.

LAURA SIGLER dated Urban for eight years and believes the former crack addict will not commit to a longterm relationship with the Hollywood superstar, despite their reported engagement over the US Thanksgiving weekend last month (NOV05).

She says, "Nicole and Keith might date for a while, but it won't last very long. I don't know her but I know him very well."

Sigler, 35, has not seen the New Zealander singer since they split in 2002.

She adds, "It's been hard. There were a lot of lows with the drugs. I don't have any dark past - he was probably the darkest part, but I'm on my own now and I'm happy about that.

"He's Keith Urban. He's everywhere. I'm trying to move on."