Rosie O'Donnell Is Engaged to Michelle Rounds

By Dahvi Shira

UPDATED 12/05/2011 at 05:15 PM EST • Originally published 12/05/2011 at 03:30 PM EST

Rosie O'Donnell has a lot to celebrate.

The TV star, 49, not only launched The Rosie Show on Oprah Winfrey's OWN network in October, but now she's preparing to say "I do" to girlfriend Michelle Rounds.

She broke the news to her audience Monday during a break set aside for commercials during the taping of her show in a Chicago studio. Her rep later confirmed it to PEOPLE.

On Friday, she posted a photo of Rounds on her Instagram page with the word "love." She also Tweeted a link – this time with the caption "happy – in love" – of her new fiancée the same day.

PHOTO: Michelle & Rosie Show Off Engagement Ring

The duo met earlier this year at a Starbucks. In October, O'Donnell joked that her "gaydar was way off" because she thought Rounds was heterosexual and just 28 years old, when really she is a gay woman and 40.

"It's fun and very exciting," O'Donnell recently said about the relationship. "I did not expect it."