Girlfriend: I Let Blake Fielder-Civil Sleep With Amy Winehouse

Aspin said that while she was already "deeply in love" with Fielder-Civil, he'd convinced her to let him sleep with the Grammy winner, because Winehouse was in a "vulnerable" state.

She added that while Fielder-Civil did not tell Winehouse about their relationship, she was certain the singer knew what was going on. Still, despite the love triangle, the two hit it off when they'd crossed paths.

Aspin said she "was so excited to meet her, and yet aware she was really my love rival ... she was so lovely and polite and called me ‘pretty girl.'"

She said Winehouse came off as "so tiny and vulnerable.

"She looked so lost ... I just wanted to hug her," Aspin, 33, said. "Though they slept in the same bed, Blake assured me they didn’t do anything. The next day she left and I never saw her again."

Aspin said she doesn't regret making the sacrifice, and thinks it helped her relationship in the big picture.

“Looking back, maybe I acted a bit of a doormat, but I understand the deep feelings they had for each other and I didn’t want to upset Blake or Amy," she said. "One of the reasons Blake and I have stayed together is because I’ve been so understanding."

Fielder-Civil's currently serving a 32-month sentence at Leeds' Armley Jail in connection with his June conviction for burglary and possessing an imitation firearm. He has a 10-week-old baby with Aspin.

Winehouse was found dead at just 27 at her London home July 23; her autopsy was conducted last week, and toxicology results will be available in 1-to-2 weeks.

Police called her death "unexplained," adding that speculation about a drug overdose is "inappropriate" in light of the fact that no drugs were found at Winehouse's house upon inspection.