Demi Moore is not letting the troubles surrounding her marriage stop her from working. The 48-year-old actress attended the NYC premiere of her latest film Margin Call Tuesday night at the Landmark Sunshine Cinema. Demi donned a striking red Zac Posen dress, and look even thinner than usual, leading to speculation that Ashton Kutcher's alleged affair has caused her weight loss.

Demi stars opposite Kevin Spacey, Zachary Quinto, Jeremy Irons and a slew of other A-list actors in the thriller that centers around the key people at a investment bank over a 24-hour period during the early stages of the financial crisis.

Unfortunately, the state of her marriage to Ashton, 33, has received more headline play than her role in the film.

In the wake of Ashton's alleged affair with 23-year-old party girl Sara Leal, the status of the couple’s relationship has been at the center of a media firestorm.

In our latest issue of OK!, a source close to the situation says that while the couple was once very much in love, things have changed.

“It was obvious from the beginning that Ashton and Demi had incredible chemistry,” the insider tells OK!. “He put her on a pedestal and basically did anything and everything to show he was worthy.”

“In many ways, it was a fairy-tale romance,” the source adds. “But that has drastically changed.”