Maria Shriver was at dinner with one of her closest friends – Oprah Winfrey – when she learned her estranged husband was going public with his infidelity and love child, RadarOnline.com has learned exclusively.

Shriver was accompanied by her daughters Katherine, 21, and Christina, 19, when she joined Oprah, Stedman Graham, Gayle King and other A-List celebs at Chicago’s RL restaurant. It was intended as a friendly dinner prior to Maria’s appearance on Oprah’s grand finale show.

PHOTOS: Arnold Schwarzenegger & Maria Shriver Through The Years

G'day Oprah!

PHOTOS: Oprah & Her Audience In Australia

The queen of daytime talk arrived in Australia Tuesday and posed with a cuddly koala named Elvis.

Winfrey -- who  flew by private jet to the land Down Under -- traveled separately from her 300 audience members who arrived earlier Tuesday in Sydney. They flew by commercial plane.