The How to Lose Friends & Alienate People star was set to marry Bruce Cummings this summer (11) but she admitted in August (11) that the big day had been postponed because she couldn't handle the stress of organising the ceremony.
Stilley has now confirmed the wedding is off because she and Cummings have parted ways.
She tells Britain's Daily Telegraph, "I haven't set a date for the wedding as I'm not engaged any more. I'm single, happy and moving on."
The How to Lose Friends & Alienate People star was set to exchange vows with businessman boyfriend Bruce Cummings in June (11), but the date was pushed back.
And Stilley has now revealed she became overwhelmed by the amount of planning involved for her big day.
She tells Britain's Daily Telegraph, "I can't be bothered with getting married. It's too much work. I'm not interested in doing it until I can afford to have someone arrange everything for me.
"All the wedding stuff just gives me such a headache (but)... I'm sure the wedding will happen eventually."
"Mine is going to be huge. It just keeps getting bigger and bigger. We were originally planning a small wedding, but soon realised that was not going to happen." Actress Margo Stilley has grand plans for her June (11) nuptials. The star will marry businessman Bruce Cummings in London.
The 9 Songs star had signed up to play Lady Thelma Furness in the new movie which tells the story of Britain's King Edward VIII, who abdicated the throne after falling in love with American divorcee Wallis Simpson.
The Material Girl will take the director's chair for the second time to tell the story of the former British monarch, but she is now looking for a new star to take over Stilley's role after the actress dropped out.
Stilley tells Britain's Sunday Telegraph, "I had the role, but we had artistic differences. She (Madonna) is really something. I wish the cast luck because they are all really talented."
The film, which stars Abbie Cornish and James D'Arcy, is slated for a 2011 release.