The pair became romantically linked over the summer (15), but the comedienne's representative was quick to shoot down the claims, insisting their relationship was strictly platonic.
O'Donnell's publicist, Cindi Berger, states, "They've been friends for several years since they met in Chicago when Rosie did a show for (Oprah Winfrey's TV network) OWN and Tatum did a docu-series for OWN."
However, the rumours haven't gone away, and now it appears the two women have holed themselves up at O'Donnell's waterfront home in West Palm Beach. Tatum is bouncing back from a small knee operation and the TV star is recovering from a minor heart procedure, three years after she suffered a near-fatal cardiac arrest.
The Paper Moon actress shared two photos from O'Donnell's property on Instagram after arriving on Tuesday (15Sep15), and captioned one snap of a windy beach, "#vacations my wife and I woo woo (sic)!!!"
Tatum did not mention O'Donnell by name, but the second picture she uploaded - of the Intracoastal Waterway - is the same highway where the TV star's home is located. She purchased the property in July (15) for $4.98 million (£3.11 million), according to Britain's Daily Mail.
Tatum has since deleted both posts, but not before responding to one Twitter follower, who asked if she was "hitched", replying, "no it was a joke".
The Oscar winner 'came out' as bisexual in May (15), revealing she is "dating mostly women", and in the September (15) issue of Harper's Bazaar, she admitted she hadn't romanced a man in over two years, adding, "In the physical sense, I'm not attracted to men right now at all.
"Now I'm clean and aware and alive and interested in the world, saying: 'Dating women is exciting to me, and this is turning me on.'"
The 51 year old was previously married to retired tennis star John MCEnroe, with whom she has three children.
O'Donnell, 53, filed for divorce from her second wife, Michelle Rounds, earlier this year (15) after less than three years of marriage.
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