(CNN) -- It's water under the bridge, but there's a reason why Rosie O'Donnell never appeared on Ellen DeGeneres' talk show.During a recent appearance on "Watch What Happens Live with Andy Cohen," Cohen mentioned how much he loved the "Lebanese" moment O'Donnell had with DeGeneres on the former's talk show.Cohen was referencing DeGeneres' 1996 appearance on O'Donnell's daytime talk show in which the two playfully danced around speculation about DeGeneres being gay.
She formally came out months later.Cohen then asked O'Donnell why she had never appeared on "The Ellen DeGeneres Show" that ended its run in May after 19 seasons."After my show went off the air, and her's was coming on the air, Larry King was on with Ellen and he said, 'Whatever happened to Rosie O'Donnell?
Her show went down the tubes. She came out as a lesbian and disappeared,'" O'Donnell explained. "And Ellen said, and I'm quoting, 'I don't know Rosie.
We're not friends.'"O'Donnell said she watching with her then wife Kelli Carpenter, whom she asked, "Did I just hear that or was that, like, a hallucination auditory voice?""I'm like, no," O'Donnell said. "And that's what happened.