The 47-year-old writer said on Instagram that she and girlfriend Rayya Elias celebrated their love with family and friends Tuesday in New York amid Elias' battle with pancreatic and liver cancer.
"Over the last year, Rayya Elias and I have been through some really difficult days together -- but not today. Today was precious and perfect. A simple and spontaneous ceremony of love, surrounded by a small handful of friends and family," Gilbert wrote.
"Our ceremony was nothing legally binding (no need to alert the authorities, folks!)...just a quiet and private celebration of what we have long known to be true: We belong to each other," she explained.
"More difficult days are to come. It doesn't get easier from here. Her illness is grave. But our love is strong. We will walk together as far as we can go together. After that, it all gets turned over to God," the star said.
Gilbert confirmed her relationship with Elias, her longtime best friend, in September after splitting from husband Jose Nunes in July.
She said she realized she was in love with Elias after her friend's cancer diagnosis.
"Death -- or the prospect of death -- has a way of clearing away everything that is not real, and in that space of stark and utter realness, I was faced with this truth: I do not merely love Rayya; I am in love with Rayya," the author wrote on Facebook.
"Rayya and I are together. I love her, and she loves me. I'm walking through this cancer journey with her, not only as her friend, but as her partner. I am exactly where I need to be -- the only place I can be," she added.
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