Lily Allen plans to marry boyfriend Sam Cooper on June 11 in Gloucestershire, England and is not happy about how the press obtained the information.
The cards feature a black and white photo that appears to have been photoshopped and showcases the 25-year-old British pop singer and Cooper, a 32-year-old business owner, sitting on a farm tractor.
The same day, Allen informed her fans that her own vintage fashion line, produced under the Lucy in Disguise label she co-founded with her sister Sarah Owen, will debut on April 18.
Their store is featured in the documentary "Lily Allen: From Riches to Rags," which airs on Channel 4 in the United Kingdom.
Allen and Cooper became engaged in December 2010, weeks after she suffered a miscarriage. The two had been linked together since July 2009.
Allen announced in August that she was expecting her first child with Cooper but suffered a miscarriage in early November. She was six months pregnant when she lost her baby for the second time.
Following the miscarriage, Allen was treated for septicemia, a blood poisoning condition that can occur when fetal material left behind in the womb becomes infected.
Allen also suffered a miscarriage in 2008 during her relationship with musician Ed Simons of the group the Chemical Brothers.