O'Donnell, 55, revealed to Howard Stern that she met the police officer at a charity event in Boston while she was in town to film her new series, SMILF.
While she made it clear that she doesn't want to remarry, she has already said "I love you" to Rooney, 32, telling Stern: "We're lesbians. That's like week two."
O'Donnell's only complaint so far is that "she doesn't know Barbra Streisand."
She later added on her website that she has only met Rooney's father, as her mother is deceased.
She did not reveal how she plans to celebrate Rooney's birthday next month.
The Worcester, Mass. police officer first posted a photo with the former talk show host in August.
Meanwhile, O'Donnell made headlines after her ex Michelle Rounds was found dead surrounded by pill bottles in September. Her estranged daughter Chelsea announced her pregnancy that same month.
What do you think of O'Donnell's new girlfriend? Sound off in the comments!
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