Pal: Maria Shriver Reeling from “Humiliating” Scandal

 Dr. Billy Ingram/

How could she not have known?

Maria Shriver's friends and supporters were beyond shocked to learn of Arnold Schwarzenegger's betrayal — a secret love child, now reportedly 13 years old, conceived with a household staff member (said to be housekeeper/assistant Mildred Patricia Baena).

And although Shriver, 55, put on a brave face for pal Oprah Winfrey on Tuesday to honor the end of her talk show, the veteran TV journalist is understandably upset behind closed doors.

"You have no idea how humiliating this is for her," a source close to Shriver tells Us Weekly. Her husband of 25 years broke the news to her in January, and Shriver moved out of the family home soon thereafter. They finally announced their separation last week; with Schwarzenegger acknowledging the child early Tuesday.

"She's a hugely prideful person," adds the insider, explaining that Shriver, transforming herself into a political wife eight years ago, stood by her man's side amidst earlier allegations of sexual misconduct with other women.

"She spent a lot of time on the [California governor] campaign defending Arnold's character -– and instructed her staff to do so as well," the source says.

"It was her primary role to clean his image and tell people 'You don't know Arnold like I do.'"

Although Shriver "suspected that [Arnold] messed around," the source says, "she had no idea about the child. She did not know until recently completely. It's beyond hurtful. She considered Arnold an excellent father and can't believe any of this is happening now."

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