"It's come to a kind and tenderhearted end," Roberts told CBS Late Night host David Letterman on Tuesday in what marked the first time she has spoken publicly about the split.
Roberts, 33, didn't go into why the two sweethearts, who dated for about four years, broke up, but had only kind words about her former leading man.
"OK, here's the thing: I love Benjamin. He's a good man, he's a fine man. He is, to the exultation of the female single population, not my man anymore," Roberts said.
In response to the rumors of George Clooney being the reason for the breakup, Roberts said she wasn't going out with the actor who starred in the television series "ER."
"A kind and lovely man, though not my boyfriend," Roberts said of Clooney. "I'm single."
And she blasts the media for not accepting that they could part on good terms.
People magazine had reported that Roberts' career was to blame for the breakup. It says Bratt wanted Roberts to cut back her movie making schedule and move from New York City to his home base of San Francisco. She reportedly did turn down several projects in recent months. But a source told the magazine that Bratt was putting her in conflict by making her choose between her work and him. Bratt was described as a "traditional" guy eager to start a family, and that he got more angry with each movie she made, and finally broke the relationship off.
Roberts won an Oscar award earlier this year for her lead role in "Erin Brockovich." Bratt, 37, was in TV's "Law & Order" and recently starred in "Miss Congeniality."
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