Wilde, who got divorced from her former husband Tao Ruspoli last year, told the audience at a night of monologues hosted by Glamour that she tried to pretend her relationship was fine.
According to Vulture, she said: "I felt like my vagina died. Turned off. Lights out.
"And you can lie to your relatives at Christmas dinner and tell them everything on the home front is just peachy. But you cannot lie to your vagina."
Wilde later told Vulture that women should be aware of their sexuality in relationships, saying: "Sometimes your vagina dies. Then you know it's time to go.
"There's no reason to sacrifice your womanhood and femininity for some sort of weird feeling of responsibility to something that may not be right. I feel like far too many women do that... [Men] are not allowed to be the only ones thinking with their genitals. We think with our p***ies."
Wilde also revealed that she is "blissfully, hopefully, wildly in love" with her current boyfriend Jason Sudeikis, who was in the audience, joking: "We have sex like Kenyan marathon runners."
Recent rumours suggested that Wilde and Sudeikis had moved in together, with sources claiming that they are "totally inseparable".
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